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  • 1
    Electronic Resource
    Electronic Resource
    ESR study on local conformations of polystyrene spin-adducts produced by chlorinated nitrosobenzene as a chain-scission inducer (1984)
    s.l. : American Chemical Society
    Macromolecules 17 (1984), S. 1139-1145 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00136a006
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  • 2
    Electronic Resource
    Electronic Resource
    Thermal decay of trapped electrons and other species in an organic glass by rapid-scan electron spin resonance (1970)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 74 (1970), S. 3221-3224 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100711a012
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  • 3
    Electronic Resource
    Electronic Resource
    Nuclear magnetic resonance studies on effects of ions (anions and cations) on nucleosides (cytidine and guanosine) (1975)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 97 (1975), S. 3827-3829 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00846a050
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  • 4
    Electronic Resource
    Electronic Resource
    Product analyses and crosslink mechanism of plasma-polymerized methyl methacrylate (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 1273-1284 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Plasma-polymerized methyl methacrylate (PPMMA) film was produced by a radio-frequency glow discharge of methyl methacrylate (MMA) gas with argon. PPMMA deposited under a plasma of mild energy was separated into a soluble fraction (sol-PPMMA) and an insoluble matrix (insol-PPMMA), which is highly crosslinked, by solvent-extraction and filtration. The chemical structure of the sol-PPMMA was determined by pyrolysis/gas chromatography, IR spectroscopy, 1H-NMR, 13C-NMR, and elemental analysis techniques. On the other hand, the structure of the insol-PPMMA was examined with IR spectroscopy, 13C-NMR with CP/MAS method, and elemental analysis. The crosslinking mechanism in the plasma polymerization of MMA is discussed on the basis of product analyses of the sol-PPMMA and the insol-PPMMA.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250506
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  • 5
    Electronic Resource
    Electronic Resource
    Copolymerizations initiated by mechano-radicals on particle surfaces of poly(tetrafluoroethylene) (1978)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 22 (1978), S. 2915-2924 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Mechanical fracture of solid poly(tetrafluoroethylene) (PTFE) produces main-chain scissions of the polymer, and free radicals, called mechano-radicals, are trapped on fresh surfaces generated by the fracture. These radical conversions were verified by ESR observation when several monomers - methylmethacrylate, vinylacetate, and ethylene - were brought into contact with these mechano-radical, and the copolymerizations of PTFE with these monomers were demonstrated. It was found that a new surface property, wettability of water, was added to the solid PTFE by the copolymerization with vinyl acetate, although the bulk nature of PTFE was not changed.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1978.070221018
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  • 6
    Electronic Resource
    Electronic Resource
    Polymerizations of ethylene and propylene initiated by milled metallic oxides. II. Characterizations of the mechanochemically produced polymers (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 291-298 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Polyethylene was mechanochemically produced by milling of alumina powder at room temperature in the presence of ethylene monomer. Nearly 50% of the produced polyethylene was chemically bonded with the matrix of the alumina. The other 50% of the polymer was extracted by the organic solvents. The polyethylene extracted by the hot n-heptane was characterized as having a structure similar to that of the branched polyethylene of low density, and the toluene extracted polyethylene had a structure similar to that of the high density polyethylene. The molecular weights of the mechanochemically produced polyethylene were found to distribute from 102 to 106 by gel permeation chromatography. The weight average molecular weight was estimated as 260,000 after the 3 days milling. Mechanochemical polymerization of ethylene was also demonstrated by milling of silica in the presence of ethylene monomer. Polymerization of propylene by milling of alumina under propylene atmosphere was performed. The obtained polymer was found to be an atactic by IR measurement and the molecular weight of the extracted product was determined as ≃ 400 by the vapor pressure osmometer.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1984.070290127
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  • 7
    Electronic Resource
    Electronic Resource
    Polymerization of ethylene and propylene initiated by milled alumina powder (1980)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 25 (1980), S. 1209-1216 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Generation of free radicals (mechano-radicals) by the milling of alumina powder at 77 K was demonstrated by ESR. After milling of alumina in the presence of ethylene (simultaneous milling) at 77 K, polyethylene-propagating radicals instead of the alumina mechano-radicals were detected by ESR. Also the contact of ethylene with the milled alumina converted alumina mechano-radicals into polyethylene propagating radicals at a temperature above the melting point of ethylene. The products extracted by hot toluene from the simultaneous milling were identified by IR to be polyethylene, and their molecular weights were roughly 10,000. The residues after the extraction were bonded with the alumina. Polypropylene was also produced by a similar method of milling of alumina in the presence of propylene. The obtained polyproylene was atactic, and its molecular weight was about 400.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1980.070250622
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  • 8
    Electronic Resource
    Electronic Resource
    Carbon-13 and proton magnetic resonance studies of poly(N-vinylcarbazole) in solution (1976)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 177 (1976), S. 2739-2747 
    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: Mit Hilfe der partiell-relaxierten Fourier Transformations (PRFT) Methode wurden die Spin-Gitter-Relaxationszeiten T1 von einzelnen C- und H-Atomen von gelöstem Poly-(N-vinylcarbazol) ermittelt. Der 13C-T1 Wert für das C-Atom der Methylengruppe ist ungefähr halb so groß wie derjenige für das C-Atom der Methingruppe, und die T1 Werte für die carbazolyl CH Kohlenstoffe liegen nahe bei denjenigen für die Hauptketten CH Kohlenstoffe. Die effektive Korrelationszeit für die Hauptketten C-Atome wurde aufgrund der gemessenen T1 Werte und des 13C-1H Kern Overhauser Effekt (NOE) Faktors zu ca. 0,95 ns bestimmt. Darüber hinaus weisen das durch normale Fourier Transformation (NFT) erhaltene 13C-Spektrum und der 1H-T1 Wert auf starke sterische Wechselwirkungen zwischen den seitenständigen Carbazolylgruppen hin. Die Ergebnisse zeigen anschaulich, daß das Polymere in Lösung eine starre lokale Struktur mit behinderter innerer Rotation der voluminösen Seitengruppen hat.
    Notes: Spin-lattice relaxation times T1 of individual carbons and protons were measured by the partially relaxed Fourier transform (PRFT) method for poly(N-vinylcarbazole) in solution. The 13C-T1 value of the methylene carbon is about one-half of that of the methine carbon, and the carbazolyl CH carbons have T1 values close to that of the skeletal CH carbons. The effective correlation time for the skeletal carbon is estimated as ca. 0,95 ns on the basis of the measured T1 and 13C-1H nuclear Overhauser effect (NOE) factor. Moreover, the 13C normal Fourier transformation (NFT) spectrum and proton T1 indicate strong steric interactions between the pendant carbazolyl groups in the polymer. The results demonstrate that the polymer in solution has a rigid local structure with hindered internal rotation of the bulky side-chain groups.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1976.021770915
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  • 9
    Electronic Resource
    Electronic Resource
    Ultrasonic velocity and adiabatic compressibility in polyelectrolyte solutions (1959)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 35 (1959), S. 429-440 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Ultrasonic velocities in poly(potassium methyl acrylate) solutions were measured at various concentrations. The ultrasonic frequency was (453.8 ± 0.1) kcycles/sec. The ultrasonic interferometer method was used to measure the sound velocity, the relative error of the measurement being kept within 0.1%. Moreover, the temperature variation of the sound velocity in these solutions in the dilute state was measured. While measuring the density, the adiabatic compressibilities at various conditions were estimated. It was found that both the increment of the ultrasonic velocity per unit concentration and the decrement of the adiabatic compressibility per unit concentration showed sharp maxima, at some very dilute concentration, in the case of a pure water solvent, and that these maxima disappeared when the solvent was changed from water to KCI solution. A plot of the ratio of the compressibility for solutions with pure water as solvent, to that for additions with KCI solution as solvent vs. temperature showed an inflection at a given temperature and thereafter leveled off at higher temperatures. The concentration change and temperature variation of the ultrasonic velocity and of the adiabatic conpressibility are qualitatively explained on the basis of Oosawa's theory of polyelectrolyte, solutions.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1959.1203512911
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  • 10
    Electronic Resource
    Electronic Resource
    ESR evidence for main-chain scission produced by mechanical fracture of polymers at low temperature (1975)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 13 (1975), S. 1233-1245 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: ESR spectra have been observed from several polymers (polyethylene, polypropylene, polymethylmethacrylate, polytetrafluoroethylene, and polybutadiene) which were mechanically fractured in vacuum at 77°K. The spectra permit identification of the free radicals produced in chain scission. It has been demonstrated for the polymers of the type such as polypropylene and poly(methyl methacrylate), that the mechanical fracture produces two different scission radicals in pairs, namely, The results indicate convincingly that microscopic scission of polymer chains is caused by macroscopic destruction of polymeric material. The critical molecular size for mechanical rupture of polyethylene chains was experimentally determined to be a degree of polymerization between 70 and 100. This size agrees fairly well with the value predicted from a theoretical model.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1975.180130614
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