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  • Polymer and Materials Science  (10)
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  • 1
    Electronic Resource
    Electronic Resource
    Phase relationships and thermodynamic interactions in linear polyethylene-diluent systemsPresented at the 13th Annual Meeting of the Society of Polymer Science Japan, Kyoto, Japan, June 6, 1964. (1966)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 4 (1966), S. 507-518 
    Details
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Phase equilibria between linear polyethylene and a number of organic diluents of varying type have been investigated. The diluents include aliphatic alcohols, alkyl phenols, aryl phenols, diphenyl derivatives, alkyl aryl ethers, esters, and ketones. It is found that n-octyl alcohol, n-decyl alcohol, n-lauryl alcohol, p-tert-amyl alcohol, p-octyl phenol, p-nonyl, phenol, diphenyl, diphenylmethane, diphenyl ether, benzyl phenyl ether, and anisole are Θ-solvents for linear polyethylene at temperatures between 120 and 200°C. Thermodynamic interactions are discussed in relation to the type of diluent.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1966.160040319
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  • 2
    Electronic Resource
    Electronic Resource
    Thermodynamic studies based on corresponding states theory for solutions of polystyrene in ethyl methyl ketoneDedicated to Professor Dr. ICHIRO SAKURADA on his 70th birthday (1974)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 175 (1974), S. 197-208 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die FLORYsche Theorie über das Prinzip der übereinstimmenden Zustände für Polymerlösungen wurde geprüft, indem die theoretisch berechneten Parameter mit experimentellen Ergebnissen verglichen wurden. Der osmotische Druck des Systems Polystyrol/Äthylmethylketon wurde für Polymerkonzentrationen zwischen 10 und 30% bei 10 bis 55°C gemessen. Unter Verwendung der Parameter X12 und Q12, die den erhaltenen Daten am besten entsprachen, wurden die berechneten Parameter mit den experimentellen Ergebnissen verglichen. Der Entropie-Parameter ψ1 sowie der Enthalpie-Parameter χH, 1 waren negativ und nahmen mit steigender Temperatur ab. Mit Hilfe der anpassungsfähigen Parameter X12 und Q12 gibt die FLORYsche Theorie die thermodynamischen Größen ziemlich gut wieder, obwohl eine geringe Abweichung von den experimentellen Ergebnissen zu bestehen scheint. Die SHULTZ-FLORYsche Methode zur Bestimmung der Theta;-Temperatur wurde auf der Grundlage dieser Theorie diskutiert.
    Notes: The polymer solution theory on the corresponding state principle developed by FLORY was examined by comparing the thermodynamic parameters calculated theoretically with experimental results. The osmotic pressure of the polystyrene/ethyl methyl ketone system was determined for solutions of polymer concentrations 10 to 30% at 10 to 55°C. Using X12 and Q12 parameters best fitting to these data, the calculated parameters were compared with experimental results. Both the entropy parameter ψ1 and enthalpy parameter χH, 1 were negative and decreased with increasing temperature. FLORY'S theory elucidates appreciably well the thermodynamic quantities with the use of the adjustable parameters X12 and Q12, but there seems to remain still some disagreement with experimental results. SHULTZ-FLORY'S method for determining the Θ-temperature was discussed based on this theory.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1974.021750121
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  • 3
    Electronic Resource
    Electronic Resource
    Small-angle X-ray scattering study on concentration dependence of polymer chain dimension (1977)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 178 (1977), S. 827-842 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The concentration dependence of polymer chain dimensions was studied by a new type of “tagged polymer method” in small-angle X-ray scattering. A small fraction of partially iodinated polystyrene, the tagged polymer, was mixed with polystyrene in toluene. From the excess scattering originated from the iodine, the radius of gyration of the polystyrene chain (Mv = 110000) was estimated at various concentrations. It was found that the chain dimension decreases first rapidly and then decreases gradually with increasing polymer concentration, and that, in the bulk, it coincides with the unperturbed chain dimension. The result was compared with theoretical predictions. The theories applicable to low concentrations could predict well the chain dimension upto mass concentrations of ca.0,1 g/cm3, while the theories applicable to higher concentrations could not predict well the chain dimension at high concentrations. The conformation of the polymer chain was also discussed. More compact conformations than a random coil as well as the bundle model were not supported by the results.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1977.021780319
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  • 4
    Electronic Resource
    Electronic Resource
    Change in molecular weight distribution accompanying thermal degradation of isotactic polystyrene (1966)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 90 (1966), S. 229-242 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Molekulargewichtsverteilungen von verschiedenen, thermisch abgebauten isotaktischen Polystyrolproben wurden experimentell bestimmt und mit den theoretisch für eine statistische Spaltung der Polymerketten abgeleiteten verglichen. Die Übereinstimmung zwischen den theoretischen und experimentellen Ergebnissen ist ziemlich gut. Es wurde gefunden, daß die Molekulargewichtsverteilung der ursprünglichen und der thermisch abgebauten isotaktischen Polystyrole sich durch die logarithmische Normalverteilungsfunktion darstellen läßt. Der Abbaugrad ist fast proportional der Zeit. Die Spaltung der Hauptketten scheint bis 330°C statistisch stattzufinden. Die Aktivierungsenergie für den thermischen Abbau von isotaktischen Polystyrolen bei 290-330°C beträgt 42 kcal/Mol. Die Ergebnisse des thermischen Abbaus von isotaktischen Polystyrolen wurden mit denjenigen an ataktischen Polystyrolen verglichen.
    Notes: The molecular weight distributions of isotactic polystyrene samples subjected to various degrees of thermal degradation were experimentally determined and compared with those derived theoretically for randoms scission of the polymer chains. Agreement between the theoretical and the experimental results was fairly good. It was found that the molecular weight distributions of the original and the thermally degraded isotactic polystyrene can be represented by the logarithmic normal distribution function. The degree of degradation is nearly linear with time. The scission of the main chains seems to occur at random up to 330°C. The activation energy for the thermal degradation of isotactic polystyrene at 290 to 330°C. was 42 kcal. /mole. The results of thermal degradation of the isotactic polystyrene were compared with those of the atactic polystyrene.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1966.020900122
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  • 5
    Electronic Resource
    Electronic Resource
    Conformation study on poly(L-tyrosine) in dimethyl formamide by small-angle X-ray scattering (1977)
    New York : Wiley-Blackwell
    Biopolymers 16 (1977), S. 2351-2361 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The size and shape parameters of poly(L-tyrosine) in dimethyl formamide were investigated with fractionated samples of different molecular weight by small-angle X-ray scattering. The molecular weight, the radius of gyration of the molecule as a whole, the radius of gyration of the cross section, the mass per unit length, and the length of helix molecule were determined. The molecular conformations proposed by Applequist and Pao for poly(L-tyrosine) were compared with the experimental results obtained. It was concluded that poly(L-tyrosine) exists in a form of the right-handed α-helix in dimethyl formamide.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1977.360161102
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  • 6
    Electronic Resource
    Electronic Resource
    Conformation study of poly(γ-methyl-L-glutamate) in helicogenic solvents by small-angle X-ray scattering (1981)
    New York : Wiley-Blackwell
    Biopolymers 20 (1981), S. 2499-2508 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Small-angle x-ray scattering of poly(γ-methyl-L-glutamate), [Glu(OMe)]n, in m-cresol and in pyridine was measured to determine the mass per unit length, Mq, and the radius of gyration of the cross section, 〈Sq2〉1/2. It was confirmed from the values of Mq that [Glu(OMe)]n exists in an α-helical conformation in these solvents. It was elucidated from the calculations on 〈Sq2〉1/2 that the side chains come in moderately close contact with the main chain in these solvents. It was indicated from the analysis of the outer portion of the scattering curves that the side-chain conformation varied depending on the solvent.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1981.360201203
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  • 7
    Electronic Resource
    Electronic Resource
    Conformation study on heparin by intermediate-angle X-ray scattering (1984)
    New York : Wiley-Blackwell
    Biopolymers 23 (1984), S. 995-1009 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The conformation of heparin in water was investigated by intermediate-angle x-ray scattering (IAXS). The theoretical scattering function for the coil conformation was calculated by the Monte Carlo method using the approximation of separable conformation energies and the conformation energies computed for two disaccharide pairs in heparin. From x-ray scattering in a relatively small-angle region, the conformation of heparin is not the ordered 21 helix conformation but the coil conformation obtained by the Monte Carlo calculation. It is expected, from x-ray scattering in a relatively wide-angel region, that the sulfate groups of heparin maintain about 7 Å between them.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360230603
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  • 8
    Electronic Resource
    Electronic Resource
    Configurational studies on amylose. II. Moments and distribution functions (1985)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 23 (1985), S. 1657-1669 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Statistical mechanical averages of vectors and tensors characterizing the configuration of amylose chains have been calculated. These quantities are expressed in the reference frame affixed to the first glucose unit, the x axis being situated along the O(4) - O(1) virtual bond vector, and the Y axis in the plane of the virtual bond and the O(4) - C(4) bond. The persistence vector a as defined by the average of the end-to-end vector r converges slowly to the limiting persistence vector a∞ with increasing chain length. Configurational averages of the Cartesian tensors formed from the displacement vector ρ = r - a have been computed up to seventh rank according to the generator matrix method. The density distribution functions Wα (ρ) evaluated for xu = 40 by using the three-dimensional Hermite polynomial expansion truncated at the term involving the tensor of seventh rank are approximately cylindrically symmetric about one of the principal axes of the second-moment tensor 〈ρ×2. The density distribution function Wα(ρ) is slightly asymmetric even for xu = 80.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1985.180230817
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  • 9
    Electronic Resource
    Electronic Resource
    Small-angle x-ray scattering from solution of rodlike particles with length distribution (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 1811-1819 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The scattering function of rods with a constant radius, 8 Å, and a length distribution of the Schulz-Zimm type was calculated on a computer as a model of helical synthetic polypeptide. The influence of length and length distribution on the scattered intensity of small-angle x-ray scattering was clarified. As length grows and length distribution broadens it is difficult to obtain reliable values of molecular weight and radius of gyration from a Zimm plot. The influence of length distribution on the mass per unit length, Mq, and the radius of gyration of the cross section, 〈Sq2〉1/2, from the Guinier plot of the cross-sectional factor decreases as the length increases, and reliable values of Mq and 〈Sq2〉1/2 can be obtained even for rods with wide distribution for rods more than 600 Å long. In particular, it is pointed out that the value of 〈Sq2〉1/2 is little influenced by length and length distribution.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170170623
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  • 10
    Electronic Resource
    Electronic Resource
    Configurational studies on amylose. I. Scattering functions (1984)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 22 (1984), S. 1551-1559 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Scattering functions for amylose chains have been calculated as a statistical mechanical average over eligible configurations based on the rotational isomeric state approximation. Main emphasis has been placed on an intermediate-angle range (0.1 〈 h = (4π/γ)sinθ 〈 1.0 Å-1) where the scattering function is sensitive to local chain configurations. In order to avoid overestimation of the regularity of chain configurations, the rotational isomeric states for each glycosidic bond have been defined by a set of discrete torsion angles at intervals of 5°. Pair correlation functions for atoms separated by sequences shorter than 31 glucose units are evaluated by the Monte Carlo method, while the interference for longer sequences is calculated by a series expansion in the even moments of the chain. All carbons and all skeletal oxygens are treated as point scatterers in order to incorporate all the interferences between atoms in unit pairs in the calculations. The calculated scattering function shows appreciable oscillation at intermediate angles, reflecting the characteristic helical tendency of the configurations. The Debye function is found to be inadequate in the intermediate-angle region owing to the non-Gaussian character of the distribution function and to breakdown of the assumption that the mean-square distance between a pair of atoms is proportional to the number of bonds between them, because of the bulkiness of the glucose unit.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1984.180220901
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