Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1995-1999
  • 1980-1984  (655)
  • 1983  (655)
  • Physics  (538)
  • Physical Chemistry  (117)
  • Nuclear reactions
  • 1
    Electronic Resource
    Electronic Resource
    Masthead (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983) 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550151101
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Stopped-flow determination of carbon dioxide-diethanolamine reaction mechanism: Kinetics of carbamate formation (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 1147-1160 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction mechanism of carbon dioxide with diethanolamine (DEA) is investigated using the stopped-flow method with optical detection in the ranges of concentration [DEA] = 0.111-8.4 × 10-2M and [CO2] = 2.94-5.6 × 10-3M. The comparison of the fast time-dependent light transmission change of a pH indicator with theoretical simulations of integrated rate equations requires a kinetic model in which a simple carbamate formation takes place simultaneously with hydration reactions, whose contributions are far from being negligible. A first-order reaction relative to DEA is thus found with a rate constant for carbamate formation smaller than usually predicted (110 ± 15M-1s-1 at 25°C). The equilibrium constant for the same reaction is also determined giving pKR = 5.3 at 25°C, in satisfactory agreement with values assumed so far.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550151104
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Kinetic and equilibrium study of gas-phase interconversions of 1,3,6-cyclooctatriene, 1,3,5-cyclooctatriene and bicyclo[4.2.0]octa-2,4-diene (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 1069-1080 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase equilibrium and rate constants for the isomerizations of 1,3,6-cyclooctatriene (136COT) to 1,3,5-cyclooctatriene (135COT) [reaction (1)] and bicyclo[4.2.0]octa-2,4-diene (BCO) to 135COT [reaction (-2)] have been measured between 390 and 490 K and between 330 and 475 K, respectively. The rate constant of reaction (1) obeys the Arrhenius equation \documentclass{article}\pagestyle{empty}\begin{document}$$k_{\rm 1} = 10^{10.93 \pm 0.08} {\rm exp}[- (115.9 \pm 0.7{\rm kJ}/{\rm mol})/RT]{\rm s}^{ - 1}$$\end{document} The corresponding equilibrium constant is given by the van′t Hoff equation \documentclass{article}\pagestyle{empty}\begin{document}$${\rm In K}_{\rm 1}^{\rm 0} = (0.24 \pm 0.04) + (13.78 \pm 0.15{\rm kJ}/{\rm mol})/RT$$\end{document} The strain energy of the 136COT ring is calculated to be 31.7 kJ/mol, based on the known value of 37.2 kJ/mol for 135COT, and ΔHf0(298 K) for gaseous 136COT is 196.3 kJ/mol. The rate constant of reaction (-2) obeys the Arrhenius equation \documentclass{article}\pagestyle{empty}\begin{document}$$k_{{\rm - 2}} = 10^{12.38 \pm 0.23} {\rm exp}[(- 106.9 \pm 1.5{\rm kJ}/{\rm mol})/RT]{\rm s}^{ - 1}$$\end{document} The equilibrium constant for 135COT ⇆ BCO fits the van′t Hoff equation \documentclass{article}\pagestyle{empty}\begin{document}$${\rm In K}_{\rm 2}^{\rm 0} = (- 1.20 \pm 0.02) - (0.40 \pm 0.07{\rm kJ}/{\rm mol})/RT$$\end{document} The strain energy of the BCO skeleton is calculated to be 108.3 kJ/mol, and ΔHf0(298 K) for gaseous BCO is 183.3 kJ/mol.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550151011
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Kinetic study of the reactions of the hydroxyl radical with ethane and propane (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 1111-1118 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Absolute rate coefficients for the reactions of the hydroxyl radical with ethane (k1, 297-300 K) and propane (k2, 297-690 K) were measured using the flash photolysis-resonance fluorescence technique. The rate coefficient data were fit by the following temperature-dependent expressions, in units of cm3/molecule·s: k1(T) = 1.43 × 10-14T1.05 exp (-911/T) and k2(T) = 1.59 × 10-15T1.40 exp (-428/T). Semiquantitative separation of OH-propane reactivity into primary and secondary H-atom abstraction channels was obtained.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550151014
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Methyl thiirane: Kinetic gas-phase titration of sulfur atoms in SX OY systems (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 1127-1132 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction SO + SO →l S + SO2(2) was studied in the gas phase by using methyl thiirane as a titrant for sulfur atoms. By monitoring the C3H6 produced in the reaction \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm S} + {\rm CH}_3\hbox{---} \overline {{\rm CH\hbox{---}CH}_2\hbox{---} {\rm S}} \to {\rm S}_2 + {\rm C}_3 {\rm H}_6 (7) $\end{document}, we determined that k2 ≃ 3.5 × 10-15 cm3/s at 298 K.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550151102
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Effects of ring strain on gas-phase rate constants. 2. OH radical reactions with cycloalkenes (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 1161-1177 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Relative rate constants for the gas-phase reactions of OH radicals with a series of cycloalkenes have been determined at 298 ± 2 K using methyl nitrite photolysis in air as a source of OH radicals. Using a rate constant for the reaction of OH radicals with isoprene of 9.60 × 10-11 cm3 molecule-1 s-1, the rate constants obtained were (X 1011 cm3 molecule-1 s-1): cyclopentene 6.39 ± 0.23, cyclohexene 6.43 ± 0.17, cycloheptene 7.08 ± 0.22, 1,3-cyclohexadiene 15.6 ± 0.5, 1,4 cyclohexadiene 9.48 ± 0.39, bicyclo[2.2.1]-2-heptene 4.68 ± 0.39, bicyclo[2.2.1] 2,5 heptadiene 11.4 ± 1.0, and bicyclo[2.2.2] 2 octene 3.88 ± 0.19. These data show that the rate constants for the nonconjugated cycloalkenes studied depend on the number of double bonds and the degree of substitution per double bond, and indicate that there are no obvious effects of ring strain energy on these OH radical addition rate constants. A predictive technique for the estimation of OH radical rate constants for alkenes and cycloalkenes is presented and discussed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550151105
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Recombination rates of chlorine atoms in flash photolysis of chlorine molecules (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 1235-1236 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550151109
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Complex rate law for the cerium(IV) oxidation of glycolic acid in the medium HClO4-Na2SO4-NaClO4 (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 417-432 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the cerium(IV) oxidation of glycolic acid have been studied in the medium HClO4—Na2SO4—NaClO4 at varying organic substrate (HL), hydrogen, and bisulfate ion concentrations at 25.0°C and ionic strength 2.0M. Under the experimental conditions used (0.03 ≤ [H+] ≤ 0.5M; 0.02 ≤ [HSO4-] ≤ 0.1M; 0.01 ≤ [HL] ≤ 0.1M) the observed pseudo-first-order rate constant kobs has been found to follow the complex expression where the values of the various constants have been estimated by a nonlinear least-squares method. According to this expression the oxidation process occurs significantly through three simultaneous pathways. Moreover three equilibria involving cerium(IV) and HSO4- (or SO42-) ions are important from a kinetic point of view, whereas only two equilibria involving the corresponding complexes with the organic substrate are predominant.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150503
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    The pyrolysis kinetics of ethyl esters in the gas phase. The alkyl substituent effect at the acyl carbon (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 455-459 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase elimination of ethyl 3-methylbutanoate and ethyl 3,3-dimethylbutanoate has been studied, in a static system, over the temperature range of 360-420°C and in the pressure range of 71-286 torr. The reactions are homogeneous, unimolecular, and follow a first-order rate law. The temperature dependence of the rate coefficients is given by the following Arrhenius equations: for ethyl 3-methylbutanoate, log k1 (s-1) = (12.70 ± 0.36) - (202.5 ± 4.4) kJ/mol/2.303RT, and for ethyl 3,3-dimethylbutanoate, log k1 (s-1) = (13.04 ± 0.08) - (207.1 ± 1.0) kJ/mol/2.303RT. Alkyl substituents at the acyl carbon of ethyl esters yield very close values in rates. Consequently it is rather difficult to offer some conclusion concerning the effect of these substituents.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150505
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Thermochemistry and kinetics of the reaction of methyl mercaptan with iodine (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 433-453 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The gas-phase reaction CH3SH + I2 has been studied spectrophotometrically over the temperature range of 476-604 K. It was found that the reaction undergoes H abstraction by I at ≤575 K, leading to the formation of MeSI and followed by a secondary reaction which leads to the formation of MeSSMe: Taking into consideration the effect of reaction (2), the equilibrium constant K1 (554 K) has been evaluated to be 0.025 ± 0.004. This value was combined with the estimated values S2980 (CH3SI, g) = 73.7 ± 1.0 eu and 〈ΔCp1,5540〉 = 0.87 ± 0.3 eu to obtain ΔH1,2980 = 4.03 ± 0.73 kcal/mol. This yields ΔHf2980 (CH3SI, g) = 7.16 ± 0.73 kcal/mol when combined with known thermochemical values for CH3SH, HI, and I2. A kinetic study was vitiated by the concurrent heterogeneous reaction of MeSH and I2 at lower temperatures and the rather complicated chemistry occurring at elevated temperatures. However, attempts at measuring rate constants at 554 K lead to a lower limit of ΔHf2980 (CH3S·, g) ≥ 29.5 ± 2 kcal/mol when an estimated value of A = 1010.8 ± 0.2 L/mol·s for the reactionc is used. DH2980 (CH3S-I) is estimated to be 49.3 ± 1.7 kcal/mol. The bond strengths of some divalent sulfurs and the reaction mechanisms are discussed. A crude estimate of DH0(H-CH2SH) = 96 ± 1 kcal has been obtained from the kinetic data.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150504
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 11
    Electronic Resource
    Electronic Resource
    Intramolecular hydrogen isotope effect in the pyrolysis of diethyl carbonate-1,1,1,2,2-d5 (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 461-468 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal unimolecular decomposition of diethyl carbonate-1,1,1,2,2-d5 has been examined in the high-pressure-limiting region. The observed chemistry is consistent with a simple, competitive two-channel model: The intramolecular isotope effect kH/kD has been determined, and the relative Arrhenius parameters for the two channels are given by \documentclass{article}\pagestyle{empty}\begin{document}$$ k_{\rm H} /k_D = (0.80 \pm 0.18)\,\exp [(1140 \pm 260){\rm cal/mol/RT}] $$\end{document} over the temperature range of 540-620 K. These Arrhenius parameters predict an isotope effect kH/kD = 5.4 at 300 K.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150506
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    The use of transition-state theory to extrapolate rate coefficients for reactions of OH with alkanes (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 503-504 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150509
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Masthead (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983) 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150601
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Rate of formation of toluene from ethylbenzene (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 469-474 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of formation of toluene from ethylbenzene was studied at atmospheric pressure in the temperature range of 600-725°C in conventional flow equipment. Residence times were 0.55-1.7 s, and initial partial pressures of ethylbenzene (H2O diluent) were 0.05-0.17 atm. The rate of appearance of toluene measures [1] the rate of the reaction C6H5C2H5 → C6H5CH3· + CH3·, with log k = 15.70 - 74.49 ± 3.2/θ. From the activation energy, E0 for the decomposition is estimated to be 72.2 ± 3.2 kcal/mol. The results are compatible with those of Esteban et al. [2], for which regression analysis gives log k1 = 14.79 - 70.76/θ. A composite, log k = 15.10 - 72.0/θ, fits both sets of data and is experimentally indistinguishable from Robaugh and Steina's [3] recent estimate by the VLPP technique or other estimates in the literature [4-6]. In light of the high overall conversion of ethylbenzene studied (2-80%), the industrial-type flow equipment, and the widely differing methods of characterization and analysis, the excellent agreement with the results of [2,3,5] is worthy of note. The data are compatible with current estimates of the heat of formation of benzyl radicals [6,7].
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150507
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    The thermal decomposition of n-hexane (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 475-502 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the pyrolysis of n-hexane was studied in a conventional static reactor over a temperature range of 650-840 K. The overall reaction is essentially first order with the kinetic parameters A = 1013.92 s-1 and EA = 260.3 kJ/mol. The distributions of the main products were analyzed by gas chromatography. A reaction model involving 240 elementary reactions was developed to describe the experimental rate data. The agreement of the model with experimental data was surprisingly good over a wide range of temperatures and pressures and up to medium extents of conversion. Methods for sensitivity studies based upon the quasi-stationary-state assumption (QSSA) were developed, and for a number of more detailed effects, such as self-inhibition, explanations could be given. It was also shown that the hexyl isomerization reactions influence strongly the product distribution. The outstanding capability of kinetic modeling with computer simulations in handling complex kinetic systems is demonstrated.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150508
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Kinetics of gas-phase decomposition of oxetan and oxetan-2,2-d2 (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 505-519 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The pressure dependence of the first-order rate coefficient of oxetan and oxetan-2,2-d2 decomposition has been studied in the pressure range from about 7 kPa down to 0.01 kPa at various temperatures between 673 and 758 K. Experimental data were analyzed using RRKM theory. Interpretation of the fall-off curves lends support to the high-pressure Arrhenius parameters A = 1015.42s-1 and EA = 259.5 kJ/mol derived from measurements made in the pressure-independent range. Decomposition of oxetan is found to occur via biradical intermediates. Data for the kinetic isotope effect were used to derive kinetic parameters for the ring-opening elementary steps in oxetan and oxetan-d2 decomposition.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150602
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Studies in nickel(IV) chemistry. Kinetics of the Cu(II) ion-mediated acid decomposition of tris(dimethylglyoximato) nickelate(IV) in aqueous acidic medium (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 521-536 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kinetics of the Cu(II) ion-mediated acid decomposition of tris (dimethylglyoximato)nickelate(IV), Ni(dmg)32- (dmg2- = dimethylglyoximate dianion), are reported in aqueous medium in the range of 3.6 ≤ pH ≤ 6.6 at 35°C and μ = 0.57 M. The pseudo-first-order rate constants of the disappearance of Ni(IV) kobs(M) satisfy the equation \documentclass{article}\pagestyle{empty}\begin{document}$$ k_{{\rm obs(M)}} = k_{ad} + k_{dec(M)} $$\end{document} where kad refers to the pseudo-first-order rate constants for the proton-assisted decomposition of the Ni(IV) complex determined independently and is a function of [H+], and kdec(M) to that for the Cu(II) ion-mediated route and is a function of [H+] and [Cu2+]. Both kobs(M) and kdec(M) are found to increase with increasing [Cu(II)]0, tending to attain limiting values at higher relative [Cu(II)]0. At low [Cu(II)]0 the kdec(M) is found to register a decrease with increasing pH in the pH range of 3.6-4.4, then an increase in the range of 4.4-5.76, and again a decrease in the range of 5.76-6.6. Results on the Cu(II) ion-mediated acid decomposition are interpreted in terms of a probable mechanism involving pH-dependent adduct formation equilibria involving the one-protonated and the two-protonated species of Ni(IV) and the various species of Cu(II) ion in the media, followed by rate-determining acid decomposition of the adduct(s) to give Ni(II) aq. and Cu(dmgH)2. While the two-protonated Ni(IV) complex apparently reacts about five orders of magnitude faster than the one-protonated species, the aquacopper(II) reacts about two orders of magnitude slower than the hydroxoaquacopper(II).
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150603
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Kinetics of the gas-phase reaction CH3F + I2 ⇆ CH2FI + HI: The C—H bond dissociation energy in methyl and methylene fluorides (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 569-577 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the gas-phase reaction of CH3F with I2 have been studied spectrophotometrically from 629 to 710 K, and were determined to be consistent with the following mechanism: A least-squares analysis of the kinetic data taken in the initial stages of reaction resulted in \documentclass{article}\pagestyle{empty}\begin{document}$$ \log k_4 (M^{ - 1} \cdot s^{ - 1}) = (11.3 \pm 0.1) - (30.8 \pm 0.2)/\theta $$\end{document} where θ = 4.575T/1000 kcal/mol. The errors represent one standard deviation. The experimental activation energy E4 = 30.8 ± 0.2 kcal/mol was combined with the assumption E3 = 1 ± 1 kcal/mol and estimated heat capacities to obtain \documentclass{article}\pagestyle{empty}\begin{document}$$ \Delta H_r^\circ (4,g,298K) = 30.0 \pm 1{\rm kcal}/{\rm mol} $$\end{document} The enthalpy change at 298 K was combined with selected thermochemical data to derive \documentclass{article}\pagestyle{empty}\begin{document}$$ DH^\circ ({\rm CH}_{\rm 2} {\rm F} - {\rm H}) = 101.2 \pm 1{\rm kcal/mol} $$\end{document} The kinetic studies of ĊHF2 and CH2F2 have been reevaluated to yield \documentclass{article}\pagestyle{empty}\begin{document}$$ DH^ \circ \left( {{\rm CHF}_{\rm 2} - {\rm H}} \right) = 103.2 \pm 1\,{{{\rm kcal}} \mathord{\left/ {\vphantom {{{\rm kcal}} {{\rm mol}}}} \right. \kern-\nulldelimiterspace} {{\rm mol}}} $$\end{document} These results are combined with literature data to yield the C—H, C—F, and C—Cl bond dissociation energies in their respective fluoromethanes, and the effect of α-fluorine substitution is discussed.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150607
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Induced heterogeneity, a novel technique for the study of gas-phase reactions. 2. Direct study of C—C bond scission in ethane (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 845-853 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Deliberate activation of the reaction vessel surface leads to the domination of chain termination in ethane pyrolysis by the reaction \documentclass{article}\pagestyle{empty}\begin{document}$$ (5) {\rm H} \to \frac{1}{2}{\rm H}_2 $$\end{document}As a result, chains are dramatically reduced in length, methane yields are entirely primary and larger in proportion to other products, and values of k1 \documentclass{article}\pagestyle{empty}\begin{document}$$ (1){\rm C}_2 {\rm H}_6 \to 2{\rm CH}_3 $$\end{document} can be directly determined from methane yield data without ambiguity. Experiments carried out in the temperature range of 841-913K at initial ethane pressures of 1-20 torr, without and with added nitrogen, yield the infinite pressure Arrhenius equation \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm log}k_{\rm 1} ({\rm s}^{ - 1}) = 16.52 \pm 0.44 - 87900 \pm 1760{\rm cal}/{\rm mol}/2.303RT $$\end{document}It is shown that most previously published data can be combined with those of this study to yield \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm log}k_{\rm 1} ({\rm s}^{ - 1}) = 16.63 \pm 0.18 - 88400 \pm 720{\rm cal}/{\rm mol}/2.303RT $$\end{document}Fall-off curves for k1 as a function of pressure are in good agreement with those from other laboratories. From these the relevant data for k-1 can be extracted for use in other kinetic studies.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150813
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Kinetics of the reaction F + 1,2-dibromo-1,1,2-trifluoroethane (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 891-904 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The title reaction was studied in a standard flow system with F atoms produced by RF discharge in F2-He mixture. Analysis was by gas chromatography using electron capture detection. There were two major products, identified as CF2BrCF2H and CF2BrCF2Br, plus presumably HF which was not detectable. The overall rate of disappearance of reactant was found to be of mixed one and one-half order, indicating a complex reaction. A mechanism is proposed comprising six steps and involving two radical species CF2BrċFBr (R1) and CF2BrċF2. The 300 K rate constant for the initial step F + reactant → HF + R1 is evaluated to be 2.2 × 10-13 cm3/molec·s, which fits in with rates of other saturated hydrocarbon reactants containing one hydrogen atom, thus supporting the view that in this class of reactants the rates of reactions of the type F + saturated hydrocarbon depend mainly on the number of hydrogen atoms in the reactant.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150905
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 21
    Electronic Resource
    Electronic Resource
    Electron transfer to trans-dihydroxotetraoxoosmate(VIII). II. Kinetics of the oxidation of dimethylsulfoxide in aqueous alkaline media (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 881-890 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the oxidation of dimethylsulfoxide by oxohydroxoosmate(VIII) complex ions in alkaline media follow pseudo-first-order disappearance in Os(VIII). The values of the observed pseudo-first-order rate constant are linearly dependent on initial dimethylsulfoxide concentrations in a fortyfold range, and increase with increasing [OH-], leveling off at higher relative [OH-]. The results are interpreted in terms of outer sphere interactions involving dimethylsulfoxide and various species of the Os(VIII) complex. The more nucleophilic dihydroxotetraoxoosmate(VIII) ion reacts about 50 times faster than the trihydroxotrioxoosmate(VIII) species.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150904
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 22
    Electronic Resource
    Electronic Resource
    Erratum (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 941-941 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150909
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 23
    Electronic Resource
    Electronic Resource
    High-temperature determination of the rate coefficient for the reaction H2 + CN → H + HCN (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 915-923 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate coefficient of the reaction \documentclass{article}\pagestyle{empty}\begin{document}$$(2){\rm H}_2 {\rm CN} \to {\rm H} + {\rm HCN}$$\end{document} has been determined in the temperature range of 2700-3500 K using a shock tube technique. C2N2—H2—Ar mixtures were heated behind incident shock waves and the early-time CN history was monitored using broad-band absorption spectroscopy. The rate coefficient providing the best fit to the data was \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm k = (7}{\rm .5}_{ - 2.0}^{{\rm + 2}{\rm .5}} {\rm)} \times {\rm 10}^{{\rm 13}} {\rm cm}^3 /{\rm mol} \cdot {\rm s} $$\end{document} in good agreement with extrapolations of previously published low-temperature results.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150907
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 24
    Electronic Resource
    Electronic Resource
    The reaction of cyclopentyl radicals with carbon tetrachloride (1983)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 15 (1983), S. 905-913 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The photolysis of azocyclopentane in the presence of cyclopentane-carbon tetrachloride mixtures has been investigated in the gas phase. Product analysis data have been used to determine the Arrhenius parameters for the reactions \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {(4)_C - {\rm C}_5 {\rm H}_{9.} + {\rm CCl}_4 \to _C - {\rm C}_5 {\rm H}_9 + {\rm CCl}_{3.} } \hfill & {k_4 = 10^{9.0 \pm 0.6} {\rm exp}[- (10.3 \pm 1.0){\rm kcal}/{\rm mol}/{\rm RT}]} \hfill \\ {(6){\rm CCl}_{3.} + _C - {\rm C}_5 {\rm H}_{10} \to {\rm CCl}_3 {\rm H} + _C - {\rm C}_5 {\rm H}_{9.} } \hfill & {k_6 = 10^{8.4 \pm 0.4} {\rm exp}[- (10.0 \pm 0.7){\rm kcal}/{\rm mol}/{\rm RT}]} \hfill \\ \end{array}$$\end{document} The rate data for chlorine atom abstraction from CCl4 by the cyclopentyl radical were compared with available data for other alkyl radicals in both the gas and the solution phases. The results indicate that the rate constant for chlorine atom abstraction in the gas phase is fairly insensitive to the nature of the attacking alkyl radical and that the activation energy for a secondary radical is about 4 kcal/mol higher than the corresponding reaction in the solution phase.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550150906
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 25
    Electronic Resource
    Electronic Resource
    Morphology and properties of poly(vinyl chloride)-poly(butadiene-co-acrylonitrile) blends (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 11-27 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The objective of this research was to study the structure-property relationships of two poly(vinyl chloride) (PVC)-poly(butadiene-co-acrylonitrile) (BAN) blends which exhibit differences in blend compatibility. Studies were carried out utilizing differential scanning calorimetry, dynamic mechanical testing, stress-strain, transmission electron microscopy (TEM), and infrared dichroism experiments at different temperatures. The BAN 31/PVC (BAN containing 31% acrylonitrile) system is considered to be nearly compatible as evidenced by Tg shifts, stress-strain results, orientation characteristics, and TEM micrographs. Similar experiments indicate that the BAN 44/PVC system is incompatible, and contains a mixed phase of BAN 44-PVC and a pure BAN 44 phase. The extent of heterogeneity in the compatible BAN 31/PVC system, however, plays an important role in the orientation characteristics of the blends.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210102
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 26
    Electronic Resource
    Electronic Resource
    Comparative Raman studies of molecular interactions at a dye/polymer and a dye/glass interfaceCorrected proofs received October 12, 1982 (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1-9 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Integrated optical techniques and resonance Raman spectroscopy have been combined to investigate the intermolecular interactions at dye/polymer and dye/glass interfaces. Frequency shifts and intensity changes of bands assigned to the stretching vibrations of the bridged quinoline rings of the cyanine dye chromophore have been utilized to gain insight into the relative strength of adhesive forces at the surface. Polarized Raman measurements were made to determine the orientation of the chromophores on a poly(vinyl alcohol) surface. This was done to assess the possibility of hydrogen bond formation between the ring nitrogen atoms and the polar hydroxyl groups at the surface.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210101
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 27
    Electronic Resource
    Electronic Resource
    Inclusion of mobile crosslinks and lateral crystallite growth in the theory of stress-induced crystallizationCorrected proofs received October 18, 1982 (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 45-53 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The theory of stress-induced crystallization is broadened to include a reshuffling of crosslink positions as a result of changing sizes of crystalline domains and multiple crystallites of varying lateral dimensions (i.e., lateral growth). A continuous state of equilibrium throughout the amorphous component of the stretched network is postulated and, consequently, effected by requiring crosslinks to anchor about their most probable locations, which vary continuously as crystallization changes. Such features incorporated into Flory's model of stress-induced crystallization broaden its theoretical base, placing it on a stronger, more realistic foundation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210104
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 28
    Electronic Resource
    Electronic Resource
    Crystallization under stress: A theory of fibrillar crystallizationCorrected proofs received October 18, 1982 (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 55-63 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A theory of crystallization in stretched polymer networks is developed. In it, four principal features are incorporated: (i) crosslinks are displaced by growing crystallites, (ii) network chains are constrained to positions compatible with fixed sample shape and volume, (iii) some network chains remain amorphous, and (iv) the relative direction of a chain through a crystallite may not be the same for all chains. The derived network force exhibits a V or U shape with changing temperature in the crystallization zone that is a close replica of the behavior of gutta percha networks. Postulates of fibrillar-lamellar transitions are not introduced into the calculations.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210105
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 29
    Electronic Resource
    Electronic Resource
    Structure-property relationships in polycaprolactone-polyurethanes (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 65-95 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The structure-property relationships of polycaprolactone-based segmented polyurethanes were studied using differential scanning calorimetry (DSC), small-angle x-ray scattering (SAXS), wide-angle x-ray diffraction (WAXD), dynamic mechanical, and stress-strain testing. The materials studied varied in hard-segment type [4,4′-diphenylmethane diisocyanate/butanediol (MDI/BD) or 4,4′-dicyclohexyl methane diisocyanate/butanediol (H12MDI/BD)], soft-segment molecular weight (830 or 2000 MW polycaprolactone), hard-segment content (23-77% by weight), and thermal history. The materials with aromatic (MDI/BD) hard segments had semicrystalline hard-segment domains, while the materials with aliphatic (H12MDI/BD) hard segment had mostly amorphous domains. Materials with the shorter polycaprolactone soft segment (830 MW) exhibited thermal and mechanical behavior which indicated a considerable degree of hard- and soft-segment compatibility. The materials which contained a 2000-MW polycaprolactone soft segment exhibited better-defined microphase separation. SAXS was used to characterize the microphase structure of each system. The effects of hard-segment content and soft-segment molecular weight were similar for the aromatic (MDI) and aliphatic (H12MDI) hard-segment-based block copolymers. Changing the hard segment from aromatic to aliphatic gave materials with larger interfacial area and slightly higher tensile strength. A range of morphologies between isolated hard domains in a rubbery matrix and isolated rubbery domains in a hard matrix was observed.
    Additional Material: 19 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 30
    Electronic Resource
    Electronic Resource
    Radiation chemistry of polybutadiene and butadiene-styrene block copolymers. II. Kinetics and mechanisms of free-radical decay reactions (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 111-121 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The decay of free radicals produced in polybutadiene, polystyrene, and block copolymers of butadiene and styrene by γ irradiation at 77 K has been studied at -110°C in the case of polybutadiene and at -95°C for the other samples. The free-radical decay rate is best interpreted in terms of an equation based on a second-order decay mechanism of a fraction of the free radicals decaying in the presence of other nondecaying free radicals. Hydrogen gas accelerates the free-radical decay. Increase of radiation dose increases the fraction of the radicals that decay, while increase of the fraction of styrene segments decreases the decaying fraction. In pure polybutadiene the higher the cis content, the greater fraction of decaying free radicals, but the second-order decay constant is less in the high-cis-content polybutadiene and is also less at the higher dose, probably owing to the hindrance of the radiation-produced crosslinks on the free-radical decay. The decrease of the second-order constant with increase of dose is also true for all the block copolymers studied.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210108
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 31
    Electronic Resource
    Electronic Resource
    Phase transitions in mesophase macromolecules. VI. The transitions in poly(oxy-2,2′-dimethylazoxybenzene-4,4′-diyloxydodecanedioyl) (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 141-150 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The transitions of poly(oxy-2,2′-dimethylazoxybenzene-4,4′-diyloxydodecanedioyl) (PDAD) have been analyzed by differential scanning calorimetry, optical microscopy, and light scattering. The mesophase glass devitrifies at 288 K [ΔCp = 220 J/K mol]. Crystallization from the liquid mesophase can be described between 322 and 362 K by an Avrami expression with an exponent between 3 and 4. Results of light scattering and optical microscopy are in accord with a spherulitic morphology grown after athermal nucleation. Melting of the semicrystalline samples (crystallinity up to 58%) occurs at about 391 K. The heat of fusion of the completely crystalline sample is calculated to be only 13.55 kJ/mol. The mesophase to isotropic phase transition occurs at 418 K with a heat of transition of 4.1 kJ/mol. A general discussion of these transitions is given.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210110
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 32
    Electronic Resource
    Electronic Resource
    The effect of deuteration on the phase equilibrium of the polystyrene/poly(vinyl methyl ether) blend system (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 159-162 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210112
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 33
    Electronic Resource
    Electronic Resource
    Properties and chain flexibility of poly(tetrahydro-4H-pyranyl-2-methacrylate)Corrected proofs received November 22, 1982 (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 189-195 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The dilute-solution properties of six poly(tetrahydro-4H-pyranyl-2-methacrylate) (PTHPM) fractions covering the molecular weight (Mw) range 4.8 × 104 to 8.4 × 105 (Mw/Mn = 1.2-1.4) were studied in tetrahydrofuran, a good solvent, and in isobutanol, a θ solvent a t 30.5°C as determined by light scattering from the A2 vs. T plot. The unperturbed dimensions were calculated from a low-angle laser light-scattering and intrinsic-viscosity data. The results indicate that PTHPM is less extended chain than poly(cyclohexyl methacrylate) (PCyM). The higher flexibility of PTHPM parallels the lower T, (57°C) of this polymer relative to PCyM (66°C).
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210202
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 34
    Electronic Resource
    Electronic Resource
    Miscible blends prepared from two crystalline polymers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 233-240 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Differential scanning calorimetry was used to determine the miscibility behavior of several polyester/Saran blends, the two polymers forming these blends being semicrystalline. It was found that Saran is miscible with polycaprolactone (PCL), polyvalerolactone, poly(butylene adipate), and poly(hexamethylene sebacate) since a single glass transition temperature Tg was observed at each composition. However, immiscibility was found between Saran and poly(ethylene adipate), poly-(ethylene succinate), poly(β-propiolactone), and poly(α-methyl-α-n-propyl-β-propiolactone) since two Tg's were recorded at several compositions. Blends were then obtained containing, over a wide range of composition, a miscible amorphous phase and two different types of crystals. From melting-point depression data on PCL and Saran crystals, thermodynamic interaction parameters χ were calculated and found to be different for PCL-rich blends and for Saran-rich blends. This result suggests a variation of χ with composition. Saran is a polymer which does not contain α-hydrogens and its miscibility with polyesters may result from a β-hydrogen bonding interaction or a C=O/C—Cl dipole-dipole interaction.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210205
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 35
    Electronic Resource
    Electronic Resource
    Unsuccessful search for a liquid-liquid transition in compression isotherms of polystyrene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 241-249 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In a search for a liquid-liquid transition in the melt of polystyrene, we have measured and analyzed a number of compression isotherms to 1800 kg/cm2 in a relevant temperature range (1.2Tg 〈 T 〈 1.4Tg). Volume data were recorded at pressure intervals of 10 kg/cm2, i.e., at pressure intervals 5-20 times smaller than used in previous work. For the analysis the data were fitted to the Tait equation. Deviations between fits and data are small, typically 0.0004 cm3/g, but nonrandom. From the absence of any systematic shifts of the nonrandom deviation patterns with temperature, we conclude that the deviations are not manifestations of a pressure-dependent liquid-liquid transition, and that there is, in fact, no evidence for the existence of such a transition in our data.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210206
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 36
    Electronic Resource
    Electronic Resource
    Concentrated solutions of polydisperse rodlike polymers in the isotropic and lyotropic liquid-crystalline phases. I. The effects of molecular length distribution on phase behavior (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 197-212 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The earlier calculations of Moscicki and Williams of the phase behavior of rodlike macromolecules in solution incorporating a Gaussian distribution of rod lengths have been extended to include, in addition to a “basic” Gaussian distribution, a small amount of high-molecular-weight species which are characterized by a δ-function or “box-function” distribution. It is shown that C*p, the concentration of polymer at which the biphasic material (isotropic plus anisotropic phase) first appears may be substantially lowered in comparison with that for the system comprising only the basic distribution. The volume fraction ΦA of anisotropic phase, the compositions of the two phases, and the distribution of species between the phases are calculated for a range of polymer concentration which spans the isotropic, biphasic, and anisotropic phase and, among several features obtained, it is shown that the high-molecular-weight species are essentially responsible for the initial formation of anisotropic phase in the biphasic system. The results of the calculations have important implications for the interpretation of published dielectric relaxation data for polyalkylisocyanates in solution at high concentration and for published shear-flow viscosity data for polyalkylisocyanates and poly(p-benzamide) in solution at high concentration and these are discussed in some detail.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210203
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 37
    Electronic Resource
    Electronic Resource
    Interdependence of motional processes in polymers: correlation functions for nmr relaxationCorrected proofs received November 22, 1982 (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 263-274 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The roles of both anisotropic motion and the interdependence of multiple motions in leading to nonexponential correlation functions for NMR relaxation data are explored. A motional model is developed in which rotational motions of segments of various lengths are controlled by the formation and disappearance of a suitable conformation. Such a model gives correlation functions which can be made, through adjustment of parameters, to be almost identical to correlation functions from other, quite different, models. The ability of NMR relaxation data to identify unique motional models is thus questioned.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210208
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 38
    Electronic Resource
    Electronic Resource
    Particle morphology in the radiation-induced heterophase polymerization of vinyl chloride with solvent added in small amounts (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 251-262 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Investigations were carried out on the polymer particle morphology obtained in the early stages of radiation-induced bulk polymerization of vinyl chloride with solvent added in small amounts over the temperature range of -10 to 70°C under quiescent conditions. At low temperatures, when the polymerization is carried out in the absence of solvent, there is flocculation of irregular aggregates of two types depending on polymerization conditions: (i) small primary particles that remain finely dispersed and (ii) large flocs that undergo rapid sedimentation. By addition of increasing amounts of solvent a gradual change towards single small spherical particles that remain finely dispersed is obtained. With more than 3% w/w THF, spherical particles in latexlike dispersions are obtained in polymerizations at -10 and 22.8°C, and show a small change in size with increasing amounts of THF. In the high-temperature range, 50-70°C, where spherical particles can be obtained in the absence of solvent, no significant changes are produced by addition of THF. The results are discussed in the terms of a marked increase in particle plasticization by the solvent, enabling the coalescence of flocculated particles of small size to occur also in polymerization at low temperature.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210207
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 39
    Electronic Resource
    Electronic Resource
    Polymorphic structure and physical properties of the polyester/ether poly(ethylene-1,2-diphenoxyethane-p,p′ -dicarboxylate) (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 275-284 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: X-ray diffraction studies of fibers of the polyester/ether poly(ethylene-1,2-diphenoxyethane-p,p′ -dicarboxylate) (PEET) produced by high-speed melt spinning show the existence of two polymorphic forms, designated α and β, in the solid state. The α form is obtained by annealing filaments melt spun at takeup speeds below 3000 m/min and is also found in samples crystallized from the melt and from dilute solutions. The α form has a monoclinic unit cell with dimensions a = 7.83, b = 10.33, c = 18.68 Å, and β = 83.1°. The equilibrium melting temperature and heat of fusion of the α form are 288.3°C and 19.1 cal/g, respectively. The β form predominates in highly oriented filaments obtained at takeup velocities above 6000 m/min. The unit cell is orthorhombic with dimensions a = 7.28, b = 5.65, and c = 18.64 Å. The β form does not transform to the α form on annealing.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210209
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    A Raman-spectroscopic study of solution-crystallized polyethylenes (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 285-294 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: An analysis of the Raman internal modes of dilute-solution-crystallized homopolymers and co-polymers of ethylene has been made, similar to the work previously reported for the bulk-crystallized polymers. The crystallite structure can be described in terms of the relative amounts of the crystalline orthorhombic phase, the liquidlike amorphous phase, and the interfacial region. These quantities change with the molecular constitution of the chains and the crystallization conditions. The level of crystallinity decreases significantly with increasing counit content as would be expected. In addition, an appreciable interfacial structure develops in copolymers as compared with the homopolymers. A possible relationship between the interfacial content and the relaxation transitions in polyethylene is discussed.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210210
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    The heat of fusion of poly(ethylene terephthalate) (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 295-299 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: By use of the Clapeyron equation for the dependence of the melting point on pressure, the heat of fusion was found to be 32.5 cal/g, in good agreement with values determined by other methods. An equation for the dependence of the melting point on the degree of polymerization gave a heat of fusion of 27.6 cal/g when applied to hydroxyl-terminated oligomers. This simple relation applied all the way down to the smallest member of the series, di(hydroxy ethyl) terephthalate.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210211
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Further annealing studies of the calcium salt of an ethylene-methacrylic acid copolymer (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 301-308 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Annealing studies of the calcium salt of an ethylene-methacrylic acid copolymer are reported. Fourier-transform infrared spectroscopy and differential scanning calorimetry were applied to the investigation of the effect of polyethylene crystallization on ionic structure as a function of annealing temperature and time. The spectroscopic changes observed in the spectra of the calcium salt annealed at 80°C differ from those seen in the spectra of the calcium salt annealed at room temperature. These changes are interpreted in terms of the multiplet-cluster model and the effect of the polyethylene-type crystallinity on the ionic microstructure.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210212
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Neutron scattering measurements of chain dimensions in polyethylene fibers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 309-317 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210213
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Chain folding in single crystals of polytetrafluoroethylene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 321-328 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Potential-energy calculations are performed in order to obtain satisfactory models for folding in single crystals of polytetrafluoroethylene crystallized in the phase stable below 19°C. The folds are assumed to be tight with adjacent reentry. Folds with a variable number of bonds are analyzed. Their conformation is deduced by a method which obtains closure between two semifolds into which each fold is decomposed. The allowed models are subsequently investigated by using an energy minimization program. Some possible models are proposed. The calculations show that the folds must be described by a number of rotational isomeric states higher than is usually assumed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210301
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Thermodynamics of mixtures of poly(tetramethylene oxide)s and 1, 4-dioxane (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 353-365 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Vapor pressures and densities of solutions of poly(tetramethylene oxide) fractions (molecular weights 650, 1000, and 2000) in 1, 4-dioxane have been determined at 30 and 40°C. The data have been utilized to determine the activities and thermodynamic functions of dilution. Excess volumes have been determined from the density data. Flory's equation of state theory quantitatively predicts the reduced residual functions X, Xh, and Xs. Predicted as well as experimental values of Xs are found to be negative. The theory predicts correctly the sign of the excess volume but quantitative agreement between theory and experiment is not obtained.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210303
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Blends of poly(butylene terephthalate) and a polyarylate before and after transesterification (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 367-378 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Blends of poly(butylene terephthalate) (PBT) and a copolyester of bisphenol-A with 50% terephthalate-50% isophthalate (PAr), before and after transesterification, have been studied by thermal and dynamic mechanical tests to determine crystallinity and phase behavior. Blends without transesterification, as prepared by solution precipitation, show a single Tg, indicating amorphous miscibility of PBT and PAr. A melting-point depression for PBT crystals is not observed; this means that PBT crystallizes excluding PAr and the entropy of melting is small. The highest fractional crystallinity for PBT is obtained at 20-35% of PAr. Transesterified blends were obtained by holding the physical blends at 250°C for up to 16 h. The transesterified systems show higher Tg's than the corresponding physical blends and also show a marked melting-point depression and lesser PBT crystallinity at the corresponding increased PAr content.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210304
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Dynamic x-ray diffraction studies of high-density polyethylene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 329-352 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Dynamic x-ray diffraction is conducted to explore the structural origin of the α and β mechanical dispersions of a melt-crystallized high-density polyethylene. It is shown that the real component of the strain orientation coefficient for the crystal c axis C′c decreases with increasing frequency at a rate which decreases with decreasing temperature. Values of C′c for the c axis are positive, C′a for the a axis negative, and C′b for the b axis close to zero, suggesting that the predominant relaxation process is crystal rotation about the b axis. The activation energy found from Arrhenius plots of C*k corresponds to that of the α1 mechanical dispersion. The dynamic birefringence in this region is dominated by the contribution from crystal orientation changes. At low temperatures, the imaginary component KC″cr of the strain-optical coefficient of the crystal phase approaches zero, while KC″am of the amorphous phase exhibits a somewhat broad dispersion peak corresponding to the β birefringence dispersion. This suggests that the principal contribution to the β birefringence dispersion arises from the amorphous phase, probably owing to the amorphous orientation process. Contrary to the case of low-density polyethylene, the dynamic crystal lattice deformation and compliance functions reveal distinct frequency dispersions corresponding to the α1 and α2 mechanical processes. The α1 lattice dispersion is thought to be associated with the α1 crystal orientation dispersion, while the α2 lattice dispersion is believed to be the inherent one arising from the onset of intracrystalline chain motions.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210302
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Phase transitions and structural properties of a thermotropic polyester (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 379-387 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The phase transition behavior and the structural properties of a thermotropic polyester, poly-(chloro-1,4-phenylene-trans-1,4-cyclohexanedicarboxylate), were studied by differential scanning calorimetry, x-ray diffraction, polarized-light microscopy, and electron microscopy. The polyester shows two first-order transitions in heating, i.e., a crystal-crystal transition and a crystal-liquid-crystal transition at 190-220 and 300-330°C, respectively. The texture in the liquid-crystalline phase is very similar to that of nematic low-molecular-weight materials. Oriented films of the polyester can be obtained from the liquid-crystalline state. Many fibrils occur in a fractured lateral surface of the film. Bandlike structures 50-100 nm wide were observed in surfaces of both oriented and unoriented films. The direction of the polymer chain axis is almost perpendicular to that of band elongation. In the oriented film, the band structures are perpendicular to the direction of orientation.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    Fourier-transform infrared study of coextrusion-drawn poly(ethylene terephthalate) (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 389-400 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The effects of initial morphology and extrusion temperature on the orientational anisotropy and conformational changes on coextrusion drawing of poly(ethylene terephthalate) (PET) have been determined by Fourier-transform polarized infrared spectroscopy. The samples were drawn from both amorphous and semicrystalline (50%) PET at 50 and 90°C. A strong influence of coextrusion drawing temperature was observed for overall chain orientation evaluated from the dichroic ratio of the 795-cm-1 band for the samples prepared from the amorphous state: this dependence was less prominent in samples drawn from the semicrystalline state. Under the same drawing conditions, the dichroic ratio for the 973-cm-1 trans band for samples prepared from the amorphous state was higher than from the semicrystalline state. Furthermore, in all samples, the relative intensity of this band was almost proportional to the degree of crystallinity. In all samples, the gauche content, evaluated from the 896-cm-1 band, decreased with increasing draw ratio. However, the dichroic ratio of this band was near unity regardless of draw ratio, initial morphology, or extrusion temperature. From these results it is considered that all gauche units in the amorphous phase are almost isotropic in the extrusion-drawn samples with overall orientation arising largely from the crystalline chains possessing totally the trans conformation (973 cm-1) in its content. In order to evaluate the deformation mechanism of the coextrusion drawing method, the relationship between the bulk and film surface orientation is also reported.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210306
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Longitudinal piezoelectric strain measurements of poly(vinylidene fluoride) films (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 765-771 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The longitudinal piezoelectric strain of poly(vinylidene fluoride) (PVF2) films has been measured at room temperature using a high-sensitivity ac capacitance-type dilatometer. The dc bias field dependence of the piezoelectric strain coefficient d33 has been determined. The polarization-related electrostrictive coefficient Q33 obtained is several hundred times larger than the value in normal piezoelectric oxide crystals and is of opposite sign.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210507
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Reversible isopentane-induced depression of carbon dioxide permeation through polycarbonate (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 753-763 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Permeability data are reported for carbon dioxide in Lexan polycarbonate at 35°C. Measurements were made for both pure carbon dioxide and for a mixed feed consisting of carbon dioxide with a 117.8-torr (0.155-atm) Partial pressure of isopentane. The effects of varying upstream CO2 driving pressure from 1 up to 20 atm were studied. The permeability to CO2 is reduced significantly in the presence of isopentane; however, the fractional depression of the CO2 permeability due to the isopentane at low driving pressures is much more significant than at high CO2 driving pressures. The well-known pressure dependence of carbon dioxide permeabilities in glassy polymers, therefore, is largely diminished by introducing isopentane to the pure carbon dioxide feed. These observations are consistent with a model for transport in glassy polymers which explains the observed trends in terms of competition between the two penetrants for microvoid sorption sites existing in the non-equilibrium glassy polymer. Exclusion of carbon dioxide from microvoid sorption sites by the more condensable isopentane preempts transport through the microvoid regions, resulting in the observed depression of the CO2 permeability.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210506
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    The elastic constants of ultradrawn polypropylene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 725-752 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The five independent elastic constants C11, C12, C13, C33, and C44 for uniaxially drawn polypropylene with draw ratios 1 〈 λ ≤ 20 have been measured from -40 to 130°C by an ultrasonic method (2.5 MHz). The crystalline and amorphous orientation functions fc and fa were also determined from wide-angle x-ray diffraction and birefringence; fc increases sharply at low λ and becomes saturated above λ = 8, but fa increases monotonically up to λ = 20. Below the glass transition temperature (ca. 60°C at 2.5 MHz) only the axial longitudinal and tensile moduli, C33 and E0, show large increase. At 110°C, however, all the moduli increase with λ; E0, E90 (tranverse tensile modulus), C44 (axial shear modulus), and C66 (tranverse shear modulus) increase 30, 3, 5, and 2.5 times, respectively, as λ increases from 1 to 20. The improvement in the mechanical properties can be attributed to the increase in the fraction of taut tie molecules which was monitored by fa. The results were analyzed in terms of the two-phase models of Takayanagi and Seferis et al. The effects of annealing were also studied.
    Additional Material: 26 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210505
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    One-dimensional models of polymer dynamics. I. Dashpot-spring models applied to a single rotor (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 773-786 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The proposion of Clark and Zimm that a dashpot and a spring can be used in place of a set of rotational barriers in polymer dynamics is studied. The simplest possible case is examined here, that of a single rotor. Reasons for altering the Clark-Zimm diffusion equation are presented and an alternative diffusion equation is proposed. The results of both diffusion equations for the correlation function 〈exp[-iθ(0)] exp[iθ(t)]〉 (θ is the angular position of the rotor) are compared with the correlation function for a rotor in an n-fold cosine potential. Although the two diffusion equations differ, both agree well with the n-fold cosine model for barriers above a few kBT. This agreement is obtained in the absence of adjustable parameters, and motivates the application of these two diffusion equations to polymeric systems.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210508
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    The effect of particle size on the haze of polymer films (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 831-833 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210512
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    Photon correlation spectroscopy of polymer solutions (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 807-820 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A polynomial subdistribution method for analyzing the correlation profile in photon correlation spectroscopy of polymer solutions is described. This method generates a continuous distribution function from the measured photoelectron time-correlation function, which can be related to particle size or molecular weight distribution of solute. The method is tested using simulated data for unimodal and bimodal distributions and compared with cumulant and histogram methods, respectively. The polynomial subdistribution method has an advantage in that it not only generates a continuous distribution curve but also works well for bimodal distributions whose peaks are close together.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210510
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    One-dimensional models of polymer dynamics. II. A dashpot-spring model (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 787-806 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The assumption of Clark and Zimm that coupled dashpots and springs can be used to model the dynamics of polymer molecules is here applied to a model different from that of Clark and Zimm. The precise differences are given in the preceding paper. The dielectric relaxation spectrum of the model is computed in time and frequency domains. The relaxation spectrum can be fitted reasonably well by the empirical Williams-Watts and Havriliak-Negami functions. The best-fit Williams-Watts and Havriliak-Negami parameters are given as functions of the parameters of the model. The model is compared with several related models found in the literature and possible interpretations are given.
    Additional Material: 21 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210509
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    The melt anisotropy of ultrahigh-molecular-weight polyethylene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 821-830 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In the course of melt-flow crystallization studies with ultrahigh-molecular-weight polyethylene (UHMWPE), we observed that the melt of UHMWPE is highly anisotropic above its equilibrium melting point and has a tendency to fibrillate. An examination of the melt anisotropy of UHMWPE by optical, Thermal, and x-ray analysis indicates that the melt anisotropy persists at 345°C, i.e., the temperature at which the polymer degrades under nitrogen, and appears similar to a smectic liquid-crystalline phase.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210511
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Dipole moments of poly(p-chlorostyrene) chains determined in toluene and isopropyl-benzene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 835-838 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210513
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Local composition effect in poly(dimethyl siloxane) solutions: A comparison of two models (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 841-849 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Two polymer solution models have been used to analyze poly(dimethyl siloxane) (PDMS) + alkane and PDMS + ketone systems. The free-volume and nonrandom interaction contributions are studied separately in order to compare the expressions for the local site fractions used in the two models. Predictions of the reduced residual chemical potential and excess volumes are discussed and compared with those found in the literature for these systems.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210601
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Densification effect on physical properties of atactic polystyrene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 851-858 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Atactic polystyrene has been densified under hydrostatic pressure, up to 2 kbar, at about 180°C. Dielectric measurements were made on densified and nondensified polystyrene samples by using the thermally stimulated depolarization current (TSDC) and the absorption and resorption current methods. The dielectric loss is modified by the densification. This effect can be explained in terms of the free-volume reduction and the internal stress induced in the material during densification.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210602
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Poly(vinylidene fluoride)-γFe2O3 magnetic composites (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 869-879 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Magnetic metal-polymer composites have been prepared by thermolysis of a metal carbonyl Fe(CO5) in poly(vinylidene fluoride). These composites comprise ca. 100-Å-diam iron-oxide, γFe2O3, ferrimagnetic particles dispersed in the polymeric matrix. Small-angle x-ray studies show that these particles have a radius of gyration in the range 63-315 Å. The composites were prepared with up to ca. 20 wt % iron and were crosslinked, as evidenced by insolubility. Electron diffraction indicating the formation of some FeF2 suggests metal-fluorine interaction during formation of the composite.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210604
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Vapor-pressure osmometry and inverse gas chromatography in the analysis of thermodynamic properties of polymer solutions (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 859-868 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The primary objective of this work is to check the utility of vapor-pressure osmometry as an experimental technique in obtaining thermodynamic data on polymer/solvent systems. The second objective is to obtain experimental values for the exchange energy parameters ΔP, X, and ζ of the theory of Sanchez and Lacombe. With respect to the first objective, solvent activities of polyiso-butylene/benzene mixtures have been measured at several concentrations up to 600 g/kg of the solvent and at two temperatures. From the activities, it is possible to determine free energies, entropies, and enthalpies and their concentration dependence. Satisfactory agreement has been found between the results obtained and data provided by other techniques such as membrane osmometry and the Cahn electrobalance. These and other data obtained by inverse gas chromatography for the same mixture in the range 35-200°C have been used in calculating the exchange energy parameter of the lattice fluid theory at different concentrations and temperatures.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210603
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Nonhomogeneous state of stress, strain, and swelling in amorphous polymer networks (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 893-905 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The total free energy of an amorphous, crosslinked polymer is given as ΔA = ΔAmix + ΔAel, where ΔAmix indicates the free energy of mixing of the crosslinked polymer and the solvent to which the network is exposed throughout the deformation process; ΔAel indicates the elastic free energy of the network as a function of strain, including the effect of dilation with the solvent. The explicit forms of the mixing and the elastic free energies are obtained from the molecular theory of rubber elasticity. Recent developments in this field allow accurate representation of the behavior of swollen networks under strain. Expressions for the stress in terms of strain and swelling ratio are obtained from the free energy. Formulation of boundary-value problems are discussed. Bending of a cuboid subject to the action of a swelling agent is analyzed as an example. Material parameters are chosen for a crosslinked amorphous network. The distribution of stresses, strains, and solvent in the bent cuboid are calculated numerically. The magnitude of moments applied at the two ends are calculated for different degrees of flexure. Results are compared with those obtained for the same network in the dry state.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210606
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Dynamic small-angle x-ray scattering from crystalline polymers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 881-892 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The variation in small-angle x-ray scattering (SAXS) for samples of crystalline polymers subjected to oscillatory strains has been observed employing the 10-m SAXS apparatus with a two-dimensional position-sensitive detector at the National Center for Small-Angle Scattering Research at Oak Ridge National Laboratory. Signal averaging has been carried out in accordance with the π/2-sector technique by gating the detection of scattered intensity in synchronism with the sample strain. In-phase and out-of-phase intensity changes have been observed for a high-density polyethylene at various frequencies (0.05-3.2 Hz) and temperatures (0-70°C). Changes are greatest at small scattering angles. Frequency dependence is greatest at lower temperatures, indicating a time-dependent response of the structural changes leading to scattering at these temperatures. The behavior is not pronounced at elevated temperatures. The similarity of the scattering at both azimuthal angles of 0° and 90° suggests the existence of an additional mechanism, perhaps microvoid formation. To evaluate void contribution, the dynamic invariant function is determined as a function of frequency and temperature. It appears that the microvoid formation lags behind the applied strain. The static and swelling SAXS studies present further evidence of void generation during elongation.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210605
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Raman scattering from the longitudinal acoustic mode of oligo-oxyethylene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 919-927 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Low-frequency Raman spectra are reported for monodisperse oligo-oxyethylenes with hydroxy and alkoxy end groups. Assignments are made to the longitudinal acoustic modes. The results are modeled by a rod with a longitudinal modulus E ≥ 2.2 × 1010 N m-2 and perturbing forces as large as (alkoxy-ended oligomers) or larger than (hydroxy-ended oligomers) those suggested for the n-alkanes.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210608
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Drawing by solid-state coextrusion of blends of atactic and isotactic polystyrene with poly(2,6-dimethyl-1,4-phenylene oxide) (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 907-918 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Atactic polystyrene (aPS)/poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) and isotactic polystyrene (iPS)/PPO compatible blends of varied composition were subjected to solid-state coextrusion. The efficiency of drawing, orientation, and crystallinity development were studied as a function of composition and draw ratio. The efficiency of drawing, as measured by elastic recovery, is high for coextrusion at temperatures ≲40°C above the glass transition temperature of the particular blend. The maximum attainable draw ratio for the blends decreased with increasing PPO concentration; the highest blend draw ratio attained was 6.5 for 25 wt % PPO. The orientation on drawing, as measured by birefringence, increased with draw but decreased with increasing PPO component at the same draw ratio. When PPO was 〈50% in iPS/PPO blends, iPS crystallized on draw. The morphology of drawn blends was studied by electron microscopy and wide-angle x-ray scattering.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210607
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Some electrophysical properties of polyphthalocyanines under the action of high pressure and shear deformation (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 929-937 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The effect of high pressure or the combined action of high pressure and shear deformation on the conductivity G and capacitance C of metal-free polyphthalocyanines (PPhCs), differing in macromolecular size, order, and degree of crosslinking, has been studied. It has been found that both G and C increase with compression. A similar phenomenon is observed under the combined action of high pressure and shear deformation on PPhC, but in this case the critical pressure needed for change in G is lower than that observed in uniaxial compression experiments. Spectroscopic investigations show that the effects of pressure and deformation on the electrophysical properties of samples under load is not connected with changes in the chemical structure of PPhC, but appear to be due to the change in the average distance between the regions of continuous conjugation. The sizes of such regions may be increased by preliminary thermal treatment.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210609
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Ionic conductivity of hybrid films composed of polyacrylonitrile, ethylene carbonate, and LiClO4 (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 939-948 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The electrical conductivity of hybrid films consisting of polyacrylonitrile (PAN), ethylene carbonate (EC), and LiClO4 was investigated. In these films, EC and LiClO4 are found to be molecularly dispersed in PAN, forming solid solutions over a wide composition range. The ionic character of the electrical conductivity is demonstrated. The conductivity is not correlated with the content of LiClO4 or of PAN, but primarily with the mole ratio [EC]/[LiClO4] in the films. An increase in the [EC]/[LiClO4] ratio enhances the conductivity. When the ratio is about 2, the conductivity attains 10-4-10-5 S cm-1 at 25°C. This change in conductivity results from a change in carrier mobility. PAN makes the films solid without decreasing the carrier mobility. In the hybrid films, the carrier mobility and the macroscopic viscosity are not related by Walden's rule. The high conductivity is due to regions in the film characterized by a low microscopic viscosity. This is determined by the mole ratio [EC]/[LiClO4] and largely controls the carrier mobility.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210610
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Radiation chemistry of linear low-density polyethylene. I. Gel formation and unsaturation effects (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 949-956 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Quenched and annealed samples of linear low-density polyethylene (LLDPE) were irradiated with 60Co γ rays in vacuo at room temperature. The data follow rather accurately Charlesby's equation s = k/r, where s is the soluble fraction, r the dose, and k a constant from which G(X), the G-value for crosslinks, was calculated. Crosslinking in the LLDPE is about twice as extensive at equal doses as in LHDPE. Production of vinylene unsaturation was approximately the same in the two types of polyethylene.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210611
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Radiation chemistry of linear low-density polyethylene. II. Kinetics of alkyl and allyl free-radical decay reactions (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 957-967 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Quenched and annealed samples of linear low-density polyethylene (LLDPE) were γ irradiated in vacuo at 77 K; the kinetics of the alkyl free-radical decay reactions were studied at room temperature, and of the allyl free-radical reactions at 60, 70, and 80°C. The ESR signals saturate at a slightly higher microwave power in the LLDPE than in high-density polyethylene (HDPE), and the alkyl radicals start decaying at a lower temperature in the LLDPE than in the HDPE. As in the HDPE the decay of the alkyl free radicals at room temperature in the LLDPE follows the kinetic equation for two simultaneous first-order reactions with the fraction of the faster-decaying component being slightly greater in the quenched than in the annealed samples. In the case of the allyl free radicals the decay at 60°C follows the equation based on one fraction of the radicals decaying according to second-order kinetics in the presence of other nondecaying radicals. At higher temperatures the data are best understood in terms of a second-order rate equation with a continuously variable time-dependent rate constant as suggested by Hamill and Funabashi.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210612
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Small-angle x-ray scattering studies of crazed glassy polymers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 969-982 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A small-angle x-ray scattering (SAXS) study of the relaxed craze structure in polystyrene was performed using the Oak Ridge National Laboratory 10-m SAXS facility. Coupled with known results from transmission electron microscopy studies, the SAXS patterns can be interpreted as scattering from an open-cell foam with void spaces interspersed among the fibrils. Results have shown the scattering centers in crazed polystyrene can be modeled as cylinders the axes of symmetry of which are parallel to the tensile axes. Scattering centers are bimodal in their size distribution, with aspect ratios of 1.0 and 2.6. Crazes in lower-molecular-weight polystyrene have more and larger scattering centers than crazes in higher-molecular-weight polystyrene, while variations in strain rate and test temperature during craze formation have no effect on the relaxed craze morphology. A comparison of SAXS patterns from polystyrene and polycarbonate indicates that the morphologies of their respective crazes are significantly different.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210613
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    An investigation of the compatibility and morphology of semicrystalline poly(ε-caprolactone)-poly(vinyl chloride) blends (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 999-1010 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Blends of poly(ε-caprolactone) (PCL) and poly(vinyl chloride) (PVC) were investigated at concentrations of PCL greater than 50 wt % using purified materials. For these concentrations, PCL partially crystallizes with degrees of crystallinity ranging from 50% for pure PCL to 〈 10% for the 50% mixture. Small-angle x-ray scattering was used to characterize the resultant morphologies. Model calculations for the interference functions and for the integrated scattering indicate that PVC is incorporated between the PCL lamellae and that the two polymers form a homogeneous mixture in the amorphous phase. These results were compared to previous results on the same system using the identical technique. Purification of the two homopolymers proved to play a critical role in the overall mixing characteristics of PVC and PCL
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210701
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    The swelling interface number as a criterion for prediction of diffusional solute release mechanisms in swellable polymers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 983-997 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: When a glassy polymer containing a uniformly dispersed solute is brought in contact with a penetrant, solute diffusion will be associated with the transport mechanism and penetration velocity of the penetrant in the polymer. Analysis and prediction of mechanisms of diffusional solute release may be obtained through a new dimensionless number, the swelling interface number, Sw, which compares the relative mobilities of the penetrant and the solute in the presence of macromolecular relaxations in the polymer. It is shown that a sufficient and necessary criterion for time-independent diffusional solute release rates from these swellable systems is that the Sw be smaller than 10-2. The swelling interface number Sw may be related to easily determined structural and thermodynamic parameters of the solute/polymer/penetrant system. Preliminary experimental results of dynamic water swelling of poly(2-hydroxyethyl methacrylate-co-methyl methacrylate) and diffusional release of theophylline from initially glassy copolymers show that decreasing values of Sw are related to increased pseudo-case-II transport kinetics of the solute.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210614
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Friction coefficients in self-diffusion, velocity sedimentation, and mutual diffusion for poly(ethylene oxide) in aqueous solution (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1029-1039 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The concentration dependences of the friction coefficient(s) for poly(ethylene oxide) have been determined on well-defined fractions in dilute aqueous solution. Three independent techniques have been used: FT-pulsed field gradient NMR (self-diffusion), photon correlation spectrosccpy (mutual diffusion), and velocity sedimentation, in the concentration range 1-25 kg m-3. The results establish that, at a given concentration, the friction coefficient in self-diffusion is appreciably smaller than that operating in mutual diffusion and sedimentation; the friction coefficient in the latter processes are identical within experimental error.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210704
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Time-dependent reactivity of species trapped in polymer matrices: Decay of allyl radicals in irradiated polyethylene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1011-1016 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Using a time-dependent rate constant of the form k(t) = Btα-1 it is possible to describe adequately the time-dependent reactivity of species trapped in polymer matrices. The constant 0 〈 α ≤ 1 characterizes the initial distribution of species: the smaller the numerical value of α the wider is the distribution related to the kinetic curve by inverse Laplace transformation. Data of Auerbach and Sanders and of Patel et al. on allyl radical decay in irradiated polyethylene are discussed.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210702
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Influence of the chemical composition and comonomer distribution on the dipole moments of 3,3-dimethyloxetane/tetrahydrofuran copolymers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1493-1500 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Experimental values of the dipole moment ratio 〈μ2〉/nm2 and its temperature coefficient d ln 〈μ2〉2/dT, where 〈μ2〉 is the mean-square dipole moment of a chain with n skeletal bonds and m2 is the mean square of the skeletal bond dipole moments, are reported for well-characterized random copolymers of 3,3-dimethyloxetane and tetrahydrofuran. The results are interpreted in terms of the rotational isomeric state theory in a manner consistent with that developed for the parent homopolymers. The theory gives a good account of the experimental results corresponding to copolymers in which the mole fraction of tetrahydrofuran lies in the range 0.11-0.89. It is found that whenever the copolymerization obeys Bernouillan statistics, the dipole moments are quite insensitive to the comonomer distribution. The theoretical analysis suggests, however, that the value of the dipole moment ratio of alternating copolymers of 3,3-dimethyloxetane and tetrehydrofuran should be near that of the parent homopolymer of lower polarity.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210816
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Low-frequency raman scattering from methylene-oxyethylene-methylene triblock oligomers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1501-1511 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Low-frequency Raman spectra are reported for monodisperse methylene-oxyethylene-methylene triblock oligomers. Assignments are made to the longitudinal acoustical modes (LAMs) of the oxyethylene block and the methylene block. The results for LAM-1 can be modeled by the vibrations of rods with perturbing forces and masses. The results for LAM-3 are not so readily modeled.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210817
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Small-angle X-ray scattering studies of microdomain structure in segmented polyurethane elastomers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1439-1472 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The small-angle x-ray scattering (SAXS) technique has been used to characterize the detailed microphase structure of two crosslinked segmented polyurethane elastomers. Both copolymers contain trifunctional polypropylene ether triols in the rubbery elastomeric block, but are synthesized with different hard segments: a symmetric 4,4′-diphenylmethane diisocyanate (MDI) chain extended with butanediol (BD); and an 80/20 mixture of asymmetric 2,4-toluene diisocyanate (TDI) and symmetric 2,6-toluene diisocyanate (TDI) chain extended with ethylene glycol (EG). Calculations of SAXS invariants and determinations of deviations from Porod's law are used to examine the degree of phase segregation of the hard- and soft-segment domains. Results show that the overall degree of phase separation is poorer in the asymmetric TDI/EG-based copolymer than in the symmetric MDI/BD-based copolymer. Determination of diffuse phase boundary thicknesses, however, reveals that the domain boundaries are sharper in the asymmetric TDI/EG system. The contrasting morphologies found in the two systems are interpreted in terms of differences in hard-soft segment compatibility, diisocyanate symmetry, and diisocyanate length. Coupled with conformational considerations, this information is used to construct a new model for polyurethane hard-segment microdomain structure. Important features of the model are that it takes into account the effects of hard-segment sequence length distribution and allows for folding of the longer hard-segment sequences back into the hard-segment domain.
    Additional Material: 24 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210814
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Spectroscopic characterization of solvent-induced crystallization of PET (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1539-1558 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Using recently developed quantitative FTIR methods, the gauche and trans conformer compositions have been measured for polyethylene terephthalate (PET) samples exposed to benzene and acetone. The kinetics of the primary and secondary isomerization stages of the solvent-induced crystallization process have been studied and compared with the thermally crystallized system. The Arrhenius activation energies of isomerization in the primary stage in which Fickian diffusion behavior is followed for the benzene- and acetone-induced PET systems are 8.2 ± 0.4 and 7.7 ± 0.4 kcal/mol, respectively.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210820
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Dynamics and mechanism of iodine sorption by polyacetylene (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1527-1537 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Sorption of iodine by bulk polyacetylene was studied under various I2 gas pressures at 25°C. The sorption dynamics show that the penetration of iodine into PA is not Fickian and the diffusion coefficient increases with time of sorption. A discontinuous increase in the sorption isotherm is observed at P/P0 = 0.25 (P is the pressure of the I2 gas and P0 is the saturation value at 25°C). It is due to iodine penetration into PA crystals, as evidenced by x-ray analysis. The distribution of iodine within crystals is apparently inhomogeneous: some unit cells are changed into “iodine-PA” cells, while others remain unchanged. The electrical conductivity depends not only on the amount of iodine but also on the I2 gas pressure under which sorption is carried out. At given iodine content, the conductivity of a sample doped under higher I2 pressure is greater than that of a sample doped under lower pressure.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210819
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Electrostatic contribution to heat capacity of polyelectrolyte solutions (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1563-1566 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210822
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    A simple, cost-effective automatic capillary viscometer system (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1559-1562 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210821
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Flow-induced crystallization by surface growth of polyethylene fibers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1513-1526 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A series of experiments has been carried out investigating several features of the surface growth method for observing longitudinal growth of polyethylene fibers in Couette geometry. Attempts to obtain limiting steady-state takeup rates using a Teflon rotor were hampered by fiber breakage; however, maximum growth rates before breakage were found to be considerably higher than those observed in previous studies. Growth rates were also obtained using a static method, and for the Teflon rotor indicated above a critical concentration a linear growth rate equal to the stirrer velocity with rates essentially independent of temperature. With a silanized glass rotor, the same method gave much lower growth rates at comparable stirrer speeds and temperatures and showed a temperature dependence suggestive of a nucleation-controlled mechanism. The implications of these results for other studies of the mechanisms of growth by the surface method are also discussed.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210818
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Carbon-13 NMR spectra of solid chlorinated polymers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1569-1572 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210824
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Elastic modulus of syntactic foams (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1567-1568 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210823
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Polymer single crystals of poly(4-hydroxybenzoate). I. Morphology (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1599-1609 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly(4-hydroxybenzoate) was prepared from 4-acetoxybenzoic acid, 4-pivaloyloxybenzoic acid, and 4-trimethylsiloxy benzoyl chloride by condensation without the addition of a catalyst. Although various reaction conditions were used the products were always crystalline. The morphology of the as-polymerized crystals has been studied by transmission electron microscopy as a function of molecular weight and end-group type. It was possible to detect morphological features during the course of reaction from oligomers to polymer which enabled us to determine the mechanisms that are likely to control chain growth for different regimes of polymerization kinetics.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210902
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Studies on dilute solutions of rodlike macroions. I. Light scattering, densitometry, and cryoscopy (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1573-1597 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Total integrated and photon correlation light scattering have been used to study two samples of poly(1,4-phenylene-2,6-benzobisthiazole) (PBT) representing two methods of precipitation to recover the polymer from the polymerization solvent. Some details of the light-scattering instrument are given. It is found that the PBT sample is rodlike, with persistence length of at least 50 nm, but that the postpolymerization processing method influences the state of interchain aggregation. The data are augmented by measurements of freezing-point depression to estimate the degree of protonation of PBT in sulfuric acid, and by measurements of partial specific volume to provide an estimate for the geometric diameter of the chain in solution. The results show a degree of protonation of 2-4 protons per repeating unit, and partial specific volumes that are appreciably smaller than the specific volume determined for the polymers. Similar data and results are reported for poly(1,4-phenyl-ene-2,6-benzobisoxazole) and poly(1,4-phenylene terephthalamide).
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210901
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Diffusion of iodine into PE and PET (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1635-1646 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: We show that the Rutherford backscattering technique is very useful for studying the kinetics of diffusion processes in polymers. We have measured the diffusion of iodine into low-density polyethylene (LDPE) by optical absorbance and by Rutherford backscattering. The optical results appear to be normal, and show no electric field dependence, but the backscattering results reveal that this is misleading, because there is fast diffusion in the bulk accompanied by large surface concentrations of iodine. We have studied PET by the backscattering technique, and in this case the behavior corresponds to a weakly concentration-dependent diffusion coefficient with no observable surface effects. Neither set of results gives support to the domain theories of low-frequency electrical oscillation in these materials.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210904
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Polymer single crystals of poly(4-hydroxybenzoate). II. A contribution to crystal structure and polymorphismDedicated to Professor H.-J. Cantow on the occasion of his 60th birthday. (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1611-1633 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Electron diffraction has been used to investigate the structure of a wide range of as-polymerized crystals of poly(4-hydroxybenzoate) [systematic name: poly(1,4-oxybenzoyl)]. The chemical composition and the degree of polymerization (DP) have been varied and some samples have been thermally treated. At room temperature two crystalline modifications with orthorhombic unit cells coexist. The chains adopt a 21 helical conformation in both forms, but there are differences for oligomer and polymer crystals. Oligomers of low DP have an extended chain-conformation, whereas in polymers a shortening of the repeat distance along the chain is observed as a function of both the DP and the crystallization conditions. From the most extensive data sets we have derived the lattice parameters a = 7.52, b = 5.70, and c = 12.49 Å for polymer crystals of phase I, and the subcell parameters for oligomer crystals of phase II a = 3.77, b = 11.06, and c = 12.89 Å. Both phases contain two chains per unit cell. In addition to modifications I and II several defect structures exist the unit cells of which contain more than two chains. At temperatures which depend on the degree of polymerization, a phase transition to a third modification takes place. The large difference between the densities of phase III as compared to both phase I and II suggests that torsional degrees of freedom exist in phase III which allow a certain mobility of the phenyl and ester groups. This mobility enables the end groups of adjacent layers in interlamellar regions of oligomer crystals to undergo transesterification reactions and therefore to increase the molecular weight of the samples.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210903
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    C-13 NMR analysis of polystyrene from low-molecular-weight model compounds (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1667-1674 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Methylene and phenyl C1 carbon signals of polystyrene are assigned on the basis of the signal assignments of styrene oligomers. Polystyrenes prepared with benzoyl peroxide, n-butyllithium, and trifluoroboron etherate catalysts have random distributions with probabilities of racemic dyads of 0.54, 0.56, and 0.45, respectively.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210907
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    The effect of dye sorption on electromechanical properties in sodium poly(L-glutamate) (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1661-1665 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Piezoelectric constant, Young's elastic modulus, and dielectric constant of undyed and dyed films of poly(L-glutamate) were measured at 10 Hz over the temperature range -120 to 120°C. The temperature of the maximum in -d″14 shifts toward higher temperature up to 0.6 mg/g polymer of dye uptake and then shifts toward lower temperature by further dye sorption. The variation of the piezoelectric modulus was interpreted by the change of mobility of impurity ions in the sample.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210906
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    An inverse gas-chromatographic study of the interaction of water with some cellulose derivatives (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1675-1689 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The sorption isotherms for water on cellulose triacetate, cellulose acetate (degree of substitution 2.45), cellulose monoacetate (degree of substitution 0.89), and ethyl cellulose were measured by finite-concentration inverse gas chromatography. The isotherms for cellulose monoacetate were also measured with a vacuum microbalance. Polymer-solvent interaction parameters and partial molar heats of sorption at zero concentration of water were estimated from the extrapolated data, but kinetic effects and isotherm curvature lowered the precision of these results. The water sorption isotherms were examined according to the Zimm cluster theory, and the results were compared to those for cellulose and (hydroxypropyl)cellulose.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210908
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Study of molecular deformation mechanisms in the glassy state. I. Temperature effect on stress-birefringence and strain-birefringence responses of poly(methyl methacrylate)The research described in this paper was performed by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1647-1660 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In order to gain better understanding of the molecular deformation processes occurring in poly-(methyl methacrylate), a series of studies was carried out in uniaxial tension on the simultaneous stress and birefringence response in both constant-strain-rate and stress relaxation experiments. The former covered the temperature range -120 to 75°C and the latter 0 to 90°C. Three deformation mechanisms, i.e., (i) change in intermolecular distance, (ii) distortion of the conformation of the COOCH3 group from its thermal equilibrium state, and (iii) orientation of main-chain segments, are invoked to interpret the experimental results. It is concluded that, in the temperature range from -120 to 75°C and possibly at higher temperatures as well, the polymer chains deform in the small-strain region by an orientation of those chain segments having lower potential-energy barriers to conformational changes and straining those chain segments having higher potential-energy barriers. Subsequent chain orientation of the already strained segments occur in the higher strain regions. Changes in intermolecular distances occur over the entire temperature range from -120 to 90°C, but their magnitude decreases gradually as the temperature increases from -40 to 40°C and then decreases sharply for temperatures above 40°C. Strain-induced distortion of the conformation of the COOCH3 group may involve only rotation of the OCH3 group around the C—O bond rather than rotation of the entire ester group itself.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210905
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    Existence of a distribution of hole-trap activation energies in FEP-Teflon (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1691-1701 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: When FEP-Teflon samples are electron irradiated at room temperature in open circuit and stored in that state for varying times following the end of irradiation, the temperature of the first current peak of the short-circuit TSC plot increases with increasing storage time. A new model is presented to explain this phenomenon, its main features being (i) a quasicontinuous distribution of hole-trap activation energies, the “center of mass” of the trapped hole population moving toward the deeper end of the distribution during the storage time, and (ii) an electron/hole recombination coefficient much smaller than that implied in an earlier model. It is shown that the assumption of a single dominant type of hole trap implies an unrealistically large frequency factor.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210909
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Nonlinear viscoelasticity and the Cox-Merz relations for polymeric fluids (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1703-1711 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: This investigation concerns the important class of fluids whose rheological properties are described by a quasilinear viscoelastic constitutive equation of the Boltzmann superposition type. The first Cox-Merz relation is closely approximated by such a fluid if its nonlinearity in shear can be described by the strain measure $ S_{12} (\gamma) = \int_0^\gamma {J_0} (\upsilon)dv $, irrespective of the distribution of its relaxation times and, hence, its linear viscoelastic properties. Here γ equals the shear strain and J0 the zeroth-order Bessel function. The second Cox-Merz relation is met by materials with a different nonlinearity, namely S12(γ) = Si(γ), where Si is the sine integral. Experimental data on melts of a polystyrene and a low-density polyethylene sample were utilized to demonstrate that both Cox-Merz relations cannot hold simultaneously.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210910
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    In-plane orientation of polyimide (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1745-1756 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: As a nondestructive method of evaluation, we have used integrated optics to investigate thin films (〈8 μm) of polyamic acid and polyimide as a function of molecular weight, initial imidization temperature, method of imidization, and annealing treatment. Polyamic acid films were found to exhibit a large optical anisotropy, indicating preferential alignment of the long axis of the molecule in the plane of the film. Imidization increased the birefringence of the film by a factor of 2.5 and reduced the film thickness. The only parameter that was found to effect the anisotropy of the films was the method of imidization. Chemical imidization was found to increase the birefringence by a factor of 3, indicative of a higher degree of molecular orientation parallel to the film surface. This effect was not observed in thicker (〉25-μm) films using x-ray diffraction where the orientation function was found to be independent of the method of imidization.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210912
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    The relationship between the physical structure and the microscopic deformation and failure processes of poly(p-phenylene terephthalamide) fibers (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1757-1783 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Relations between the physical structure and the deformation and failure processes of poly(p-phenylene terephthalamide) (PPTA) fibers are reported. The effects of the physical processes involved in fiber fabrication, including the crystallization of PPTA-H2SO4 dopes under stress, are considered in relation to their effect on the structure of the fiber. The deformation and failure processes together with the structure of the fiber are discussed in the light of fracture-topography studies of fiber-epoxy composite strands, single filaments, HCl-etched and unetched yarns, and transmission optical microscopy studies of stressed and unstressed yarns. In view of these observations, the physical structure of PPTA fibers is discussed in terms of pleated H-bond sheets, the macromolecular chain-end concentration and distribution, and the presence of impurities. The structural parameters that affect the failure processes of these fibers and how such parameters can be modified by service environment conditions are also addressed.
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210913
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Rheo-optical studies on the deformation mechanism of semicrystalline polymers. XIV. Alpha and beta mechanical dispersions of spherulitic high-density polyethylene and the dynamic orientation distribution function of crystallitesPresented at the International Symposium on Mechanical Properties of Crystalline Polymers, October 14-16, 1980, University of Massachusetts, Amherst, MA 01003. (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1713-1743 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The dynamic tensile deformation mechanism of spherulitic high-density polyethylene was investigated by dynamic x-ray diffraction at various temperatures and frequencies in order to assign the α and β mechanical dispersions explicity. The uniaxial orientation distribution function q(ζj,0) of the jth crystal plane and its dynamic response Δq′j(ζj,0) in phase with dynamic strain were observed for the (110), (200), (210) and (020) crystal planes. Then the orientation distribution function w(ζ,0,η) of crystallites (crystal grains) and its dynamic response Δw′(ζ,0,η), also in phase with the dynamic strain, were determined by a mathematical transformation procedure proposed by Roe and Krigbaum on the basis of the Legendre addition theorem. The temperature and frequency dependences of w′(ζ,0,η) were analyzed in terms of the model parameters for dynamic spherulite deformation combining affine orientation of crystal lamellae with several types of preferential reorientation of the crystal grains within the orienting lamellae. The following assignments are made: (i) The α mechanical dispersion must be assigned to the dynamic orientation dispersion of crystal grains within the crystal lamellae, involving two types of preferential rotations of the grains about their own crystal b and a axes. The rotation about the b axis is associated with lamellar detwisting, mostly in the equatorial zone of uniaxially deformed spherulites; the rotation about the a axis is associated with intralamellar shearing, mostly in the polar zone of the spherulites. Thus both rotations are intralamellar grain-boundary phenomena. (ii) The β mechanical dispersion must be assigned to the dynamic orientation dispersion of the crystal lamellae behaving as rigid bodies. It is not accompanied by reorientation of the crystal grains, but is associated with orientation dispersion of noncrystalline material between the lamellae. Thus it is an interlamellar grain-boundary phenomena.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210911
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    Small-angle x-ray scattering study of density fluctuation in pressure-densified polystyrene glasses (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1785-1796 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Densified polystyrene glasses, prepared by cooling from the liquid state under elevated pressure, were studied by small-angle x-ray scattering at ambient pressure. The density fluctuation, determined from the x-ray data, showed a decrease with increasing pressure up to about 1.5 kbar, and then leveled off to a fairly constant value. The reduction in the density fluctuation produced by the pressure is much greater than the associated decrease in the specific volume. The observed change in density fluctuation is consistent with the view that the density fluctuation in glassy polymers consists of dynamic and quasistatic components and that the first of these can be correlated with the compressibility of the glass. The present data on the density fluctuation, in conjunction with the available data on volume and enthalpy, can be interpreted to mean that in pressure-densified glasses unfavorable chain configurations are trapped in local energy minima, and the strain energy thus stored can promote segmental motion leading to volume expansion at temperatures far below Tg. Some preliminary evidence indicating the formation of microcavities in these pressure-densified glasses is also presented.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210914
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Characterization of lattice disorder in the low-temperature phase of irradiated PTFE by vibrational spectroscopy (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 21 (1983), S. 1797-1805 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In an effort to elucidate the structure of the low-temperature phase of PTFE, a spectroscopic study of the effect of progressive irradiation on the low-frequency infrared spectrum was undertaken. Previous infrared and Raman measurements indicated that irradiation of PTFE decreases its crystalline content, resulting in a lowering of the 19°C phase transition temperature due to the introduction of disorder and defect structures into the lattice by chain scission. Far-infrared studies of virgin and irradiated PTFE at liquid nitrogen temperatures show that the medium to strong bands at 45, 54, 58, and 71 cm-1, attributed to lattice vibrations, decrease in intensity as the crystalline content decreases. These findings support the assignment of these bands to intermolecular vibrations of the crystalline lattice and are an indication of the presence of more than one molecule in the crystallographic unit cell.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.180210915
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...