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  • 1
    Electronic Resource
    Electronic Resource
    Proof of the charging of polypeptides and polyamides in organic acids (1972)
    New York : Wiley-Blackwell
    Biopolymers 11 (1972), S. 661-665 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The electrophoresis of poly-γ-benzyl-L-glutamate (PBLG), poly-L-alanine (PLA) and nylon dissolved in various solvents was studied in a glass cell containing three sintered glass partitions. After the passage of a measured amount of charge the concentration of PBLG remained constant in all four chambers when the helicogenic solvents dimethylformamide and ethylene dichloride were used, but in mixtures of ethylene dichloride and dichloroacetic acid and in trifluoroacetic acid, polypeptide migrated to the cathode. Electrophoresis also occurred with PLA in trifluoroacetic acid and with nylon in formic acid. Although the total charge on the polyion could not be determined, the results show beyond reasonable doubt that polypeptides and polyamides are protonated in the presence of moderately strong organic acids.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1972.360110311
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  • 2
    Electronic Resource
    Electronic Resource
    X-Ray diffraction by amorphous polymers: Models for biological systems (1971)
    New York : Wiley-Blackwell
    Biopolymers 10 (1971), S. 777-788 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The x-ray scattering method has been used to investigate the structure in two amorphous crosslinked polymers which are regarded as test systems to establish the power of the method as applied to amorphous biologically significant polymer associations. It is shown that structural information can be determined about the rigid regions within the polymer systems, i.e., those regions held in particular configuration by stereochemical effects. Models of such regions extending over distances with dimensions of ca 18 Å are proposed for an Araldite polymer and for crosslinked poly (methyl/butyl methacrylate). The results allow some general statements about the usefulness and limitations of the amorphous x-ray method.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360100502
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  • 3
    Electronic Resource
    Electronic Resource
    Pervaporation and membrane distillation through membranes made of poly(2,6-dimethyl-1,4-phenylene oxide) (1993)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 206 (1993), S. 193-198 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Eignung von Membranen aus Poly(2,6-dimethyl-1,4-phenylenoxid) für die Trennung von Wasser-Ethanol-Gemischen mittels Pervaporation wurde untersucht. Asymmetrische Membranen entstanden durch Phaseninversion, wobei Chloroform als Lösungsmittel und 1-Butanol als Nichtlöser zur Anwendung kamen. Homogene, dichte Membranen wurden aus Lösungen des Polymeren in Chloroform durch Abdunstung des Lösungsmittels erhalten. Nichtporöse Membranen, die bevorzugt permeabel für Wasser sind, entstanden entweder durch Abdunstung oder durch Fällung aus Lösungen mit geringem Nichtlöseranteil. Mikroporöse, aus Lösungen mit hohem Nichtlöseranteil hergestellte Membranen lassen bevorzugt Ethanol permeieren, vorausgesetzt, daß die Feedlösung die Membran nicht benetzt.
    Notes: The ability of poly(2,6-dimethyl-1,4-phenylene oxide) membranes to separate water-ethanol mixtures by pervaporation was examined. Asymmetric membranes were prepared from solutions containing chloroform as a solvent and 1-butanol as a nonsolvent by the phase-inversion process. Homogeneous, dense membranes were prepared from chloroform solutions by evaporation. Nonporous membranes (membranes precipitated from solutions with a low amount of the nonsolvent or prepared by evaporation) were preferentially permeable to water. Microporous membranes (precipitated from solutions with a high amount of the nonsolvent) were preferentially permeable to ethanol, provided the membrane is not wetted by the feed solution.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1993.052060116
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  • 4
    Electronic Resource
    Electronic Resource
    Handbook of Wastewater Treatment Processes. Herausgeg. von A. S. Vernick und E. C. Walker. Marcel Dekker, Inc., New York-Basel 1982. XIV, 255 S., zahlr. Abb., geb., SFr. 114, - (1983)
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 55 (1983), S. 590-590 
    Details
    ISSN: 0009-286X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cite.330550725
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  • 5
    Electronic Resource
    Electronic Resource
    The flexibility of biphenyl and related species utilizable as molecular swivels in rodlike polymers. A CNDO/2 analysis (1982)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 183 (1982), S. 801-820 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Aromatic heterocyclic polymers are exceedingly attractive high performance materials because of their unusually high mechanical strength, chemical resistance and thermal stability, but are very difficult to process unless “swivel” atoms or groups are inserted along the chains to increase conformational flexibility. The present theoretical investigation employs the CNDO/2 method with direct geometry optimization to calculate such flexibility for the wholly aromatic swivels biphenyl, 2,2′-bipyridyl, 2-phenylpyridine, 2,2′-bipyrimidyl, and 2-phenylpyrimidine. The most important result is the prediction that both flexibility and accessibility of coplanar conformations should increase significantly with the number of ortho-CH groups replaced by N-atoms. The calculations also provide information on other conformation-dependent properties such as optimized geometries, charge distributions, and dipole moments, and these results are found to be in satisfactory agreement with the results of previous theoretical and experimental studies. Finally, since these chains are soluble only in strongly acidic media, the species mono- and diprotonated 2,2′-bipyridyl, 2,2′-bipyridyl · H3O+, and 2,2′-bipyrimidyl · 2H2O were also investigated with regard to some of these conformational characteristics.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1982.021830405
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  • 6
    Electronic Resource
    Electronic Resource
    Energy transfer in polymer films: The nylon 66-proflavine system (1969)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 7 (1969), S. 497-513 
    Details
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Triplet → singlet energy transfer in nylon 66 film (donor) dyed with proflavine (acceptor) is demonstrated by a decrease of the nylon phosphoresence lifetime and an increase in the proflavine delayed fluorescence/nylon phosphoresence ratio with increasing proflavine concentration. Although the observed donor phosphorescence decay is apparently exponential, the transfer is probably via a long-range dipole-dipole (Förster) interaction, rather than by triplet exciton migration. Arguments are advanced to support this view. Proflavine delayed fluorescence produced by a direct excitation process is also observed. The decay time for this process is roughly an order of magnitude less than that for the sensitized process. All emission intensities are shown to vary linearly with exciting light intensity. Finally, temperature dependence of proflavine delayed fluorescence under different excitation conditions is shown. The efficiency of direct excitation process increases markedly near -50°C as the temperature is increased; the sensitized delayed fluorescence intensity follows that of the nylon phosphorescence with increasing temperature, as expected.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1969.160070305
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  • 7
    Electronic Resource
    Electronic Resource
    Single point determination of intrinsic viscosity (1963)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 7 (1963), S. S30 
    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
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1963.070070436
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  • 8
    Electronic Resource
    Electronic Resource
    The grafting of isoprene onto poly(propylene oxide)Presented at the Third Northeast Regional Meeting of the American Chemical Society, Buffalo, N. Y., October 11, 1971. (1972)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 16 (1972), S. 1947-1952 
    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: The grafting of isoprene as well as a comonomer mixture of isoprene and acrylonitrile onto a backbone of high molecular weight poly(propylene oxide) with tertiary-butyl peroctoate gave a gumstock which is sulfur curable to a product having interesting elastomeric properties.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1972.070160808
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  • 9
    Electronic Resource
    Electronic Resource
    Measurement of gas permeability of polymers. I. Permeabilities in constant volume/variable pressure apparatus (1976)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 20 (1976), S. 1921-1931 
    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: A constant volume/variable pressure gas permeability apparatus is described that provides accurate determination of permeabilities ranging from less than 10-1 to 106 centibarrers. Metal construction, variable temperature control, adjustable downstream pressure and constant volume, and a differential pressure transducer with automatic recording are design features that permit detailed permeability studies under a variety of environmental conditions. Pressure effects on polymer films have been investigated up to 1000 psi, and the relation of gas concentration to permeability has been studied by varying the downstream pressure and volume conditions. The high feed pressures have significantly shortened the time required to obtain meaningful data on low-permeability materials after steady-state conditions are achieved, and the variable-temperature control has permitted evaluation of temperature-related phenomena.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1976.070200719
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  • 10
    Electronic Resource
    Electronic Resource
    Polyurethane ionomers. I. Structure-properties relationships of polyurethane ionomers (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 2467-2479 
    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: The influence of chemical structure on mechanical properties of polyurethane ionomers (PU ionomers) has been examined. NCO-terminated prepolymers prepared from primarily 4,4-methylene bis(phenyl isocyanate) (MDI) and poly(oxytetramethylene) glycol (PTMO) were chain extended with tertiary amine-containing diols and the ionomers obtained by quaternization of the prepolymers. The N-methyldiethanolamine chain extender gave the best physical properties. The mechanical properties of the PU ionomers were improved with decreasing chain length of PTMO and with increasing concentration of quaternary ammonium centers (or NCO/OH ratio of PU prepolymers). A lower degree of quaternization resulted in a decrease in the mechanical properties of the resulting PU ionomers, but their properties could be improved by post-quaternization. The adhesion of the PU ionomers to aluminum and the glass transition temperature increased with increasing concentration of quaternizing centers.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1984.070290804
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