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  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 2185-2194 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of cyclohexene oxide was investigated with a new catalyst system of Al(acac)3- silanol compounds. Catalyst activity varied with the ratio of silanol/Al(acac)3 and the structure of silanol compounds. Catalyst deactivation appeared to be caused by self-condensation of silanol and the addition of silanol to the epoxy ring. Polymer structure was investigated by 13C-NMR spectroscopy and x-ray diffraction. The mechanism of the polymerization appears to be cationic.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1652-1652 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 2541-2550 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerization of cyclohexene oxide with Al(acac)3-silanol catalyst supported by zeolite and porous silica has been investigated. Cyclohexene oxide was also polymerized to a lesser extent by a zeolite-silanol catalyst and an Al(acac)3-silica gel catalyst. The catalytic activity of the zeolite-silanol system varied with the zeolite pore size. The catalytic activity of the Al(acac)3-silanol system was enhanced by supporting the catalyst with porous silica or zeolite. The Al(acac)3-silanol catalyst supported by zeolite was especially effective in increasing polymer conversion and molecular weight. Catalytic activity increased with increasing chemical interaction between silanol and porous silica. The molecular weight of the polymers with these catalysts increased in the order zeolite-silanol〉 zeolite-Al(acac)3-silanol 〉Al(acac)3-silanol ≈ Al(acac)3-silanol supported by porous silica〉Al(acac)3-silica gel.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 2977-2985 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymerization of cyclohexene oxide, especially the catalytic activity influenced by silanol structure, was examined by using an Al(acac)3-silanol compound catalyst. The catalytic activity increased as the acidity of silanol increased. It was prolonged by sterically hindered silanol compounds which prevented the silanol from self-condensation and from joining with the epoxide. In addition, the greater catalytic activity produced by intramolecular hydrogen-bonding silanol compounds is explained by the polymer effect.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1433-1443 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new catalyst system (Ph3SiCOPh-aluminum complex-alcohol) was investigated for photopolymerization of cyclohexene oxide. Polymer conversion and molecular weight increased with polymerization time. When a Ph3SiCOPh-Al (n-Praa)3-alcohol catalyst system was used the catalyst activity decreased, depending on the alcohol: i-PrOH 〉 n-PrOH 〉 i-BuOH 〉 MeOH 〉 t-BuOH 〉 H2O. When the Ph3SiCOPh-Al complex-i-PrOH catalyst system was used the catalyst activity decreased, depending on the ligand of the Al complex: ß-ketoester 〉 orthocarbonyl phenol 〉 ß-diketone. Benzophenone derivatives were effective for catalyst activation as a photosensitizer.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 33 (1987), S. 2403-2409 
    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: The temperature dependence of the CO2 permeability coefficient in poly(vinyl acetate) (PVAc) was measured continuously by a differential permeation rate method. Tg was changed at upstream pressure in PVAc/CO2 system, and curious behavior of Ar was observed after CO2 conditioning. The differential permeation rate experiment successfully exhibits the effects of continuous temperature change for membranes with different histories.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 17 (1979), S. 1237-1250 
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Correlations between the crystal structures of polymers consisting of the hydrogen-bonded molecular sheets and anisotropy of the linear compressibility (K0) of the crystal were studied at 20°C under hydrostatic pressures up to 6 kbar. For nylon-6, it was found that K0 is more than four times larger in the direction normal to the hydrogen-bonded sheet than in the parallel direction. The inversion of the sheet direction involved in the α → γ transition of nylon-6 was clearly reflected in the anisotropy of the linear compressibility. For atactic poly(vinyl alcohol), K0 in the c-axis direction was 1.6 times larger than that in the a-axis direction, which is consistent with a structure model with the hydrogen-bonded sheet parallel to the a-axis. Theoretical calculations by Tashiro et al. indicate, however, the anisotropy does not necessarily correspond to the sheet structure when the direction of the hydrogen bonds strongly deviates from the plane of the sheet.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 75 (1964), S. 1-10 
    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: Es wurde eine Reihe von Versuchen durchgeführt, um die Gültigkeit der Annahme eines einfachen Reihen-Modells für die Berechnung des Elastizitätsmoduls der kristallinen Bereiche in orientierten linearen Polymeren mit Hilfe der röntgenographischen Messungen der Gitterdehnung zu beweisen. Von verschiedenen Proben wie Fäden, Fasern und Filmen von Polyäthylen, Polyvinylalkohol, Polypropylen, Polyoxymethylen und Cellulose wurden die Kraft-Dehnungskurven unter der obigen Annahme konstruiert und die Werte des Moduls miteinander verglichen. Trotz des Unterschiedes zwischen den Mikrostrukturen dieser Proben erhielt man fast den gleichen Gittermodul bei jedem dieser Polymeren. Die großen Unterschiede zwichen den makroskopischen Moduln der Proben hatten keinen Einfluß auf den Gittermodul. Die Gittermoduln von trockenem und mit Wasser gequollenem Polyvinylalkohol oder auch Cellulose unterschieden sich nicht voneinander. Diese Ergebnisse stellen eine starke Stütze für die oben erwähnte Annahme dar.Ferner wird die Dehnungsfähigkeit der verschiedenen Polymer-Moleküle diskutiert.
    Notes: Some experiments were carried out to prove the validity of the assumption of a simple series model for the calculation of the elastic modulus of crystalline regions in oriented linear polymers from X-ray determination of lattice extension. Various specimens such as filaments, fibers, and films were prepared from polyethylene, polyvinyl alcohol, polypropylene, polyoxymethylene and cellulose, stress-strain curves constructed under the assumption of a simple series model; and calculated values of modulus compared. In spite of the differences of microstructures of these specimens, nearly the same value for the lattice modulus was obtained for each polymer. A large difference of specimen moduli had no effect on the lattice modulus. Lattice moduli of dry and water-swollen polyvinyl alcohols or cellulose did not differ from each other. These results are a strong support for the above assumption.Extensibility of various polymer molecules was also discussed.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 14 (1970), S. 2039-2048 
    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: It has been found that tack values of pressure-sensitive adhesives are dependent on the surface energies for adherends. The parabolic curves with maxima are obtained from the plots of tack values versus critical surface tensions for the substrates. The maximum occurs at the region where the two surface tensions are almost similar. On the other hand, tack is measured as a dynamic value indicated as the force necessary to deform the adhesive mass. To explain why the tack values is controlled by the surface character of the adherend, a mechanism is proposed for adhesive bond breaking. Primarily, bonding occurs by wetting the surface with adhesive. When the adhesive bond breaks by external force, unbonding proceeds from the viscoelastic deformation of the adhesive mass around the wetted spots on the surface of the adherend. As the total area of wetted spots is determined by surface energy, the tack value is dependent on the critical surface tension of the adherend.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 14 (1970), S. 2295-2303 
    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: The presence of adhesive residue on the surface of various adherends after peeling has been confirmed using a tracer technique. Adhesive bonding is found to break by a cohesive mechanism, although the unbonding process seems apparently to be due to intersurface failure. This result supports the concept for adhesive bond breaking proposed in the preceding paper: The unbonding proceeds from the viscoelastic deformation of the adhesive mass around the wetted spots on the surface. As the number of spots in a unit area is controlled by surface energy, the tack value is dependent on the critical surface tension of the adherends.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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