GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 8 (1970), S. 207-224 
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A discussion is given of the behavior of a mathematical model chosen to approximate conditions during precipitation chromatographic fractionation of polymer (Baker Williams fractionation). With only one molecular weight species of polymer a complete solution of the mathematical model was obtained. With more than one species it was necessary to use a computer solution. Curves showing the movement of polymer containing one and two species of polymer are given for a variety of conditions of operation. It was found that the degree of fractionation of polymer approaches a limiting value with increasing length of column. Under some conditions the degree of fractionation may go through a maximum with length of column. The equilibrating distance (distance of travel of the liquid phase required to establish equilibrium of polymer between the liquid and the bed) was found to be very important in determining the fractionation.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 7 (1969), S. 163-170 
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A resolution index for gel-permeation chromatograph (GPC) columns is defined by the relation log (RI) = αW, where RI is the resolution index, α is the slope of the calibration curve of logarithm of molecular weight against peak position for narrow polymer fractions, and W is the width of the GPC curves for narrow fractions. This resolution index is calculated approximately for several GPC columns individually and in series combinations by using data obtained on narrow fractions of polystyrene. The index increases with number of columns and with flow rate over a limited range of flow rate, does not vary much with solvent, and does not correlate well with plate count obtained with low molecular weight molecules. It is believed that the resolution index provides an improved indication of the performance of GPC columns.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 6 (1962), S. 278-282 
    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: Interlaboratory comparisons on several materials are being conducted among a half-dozen laboratories having high speed tensile testers of widely different mechanical design and instrumentation. This progress report gives results from the first two round robins, the first on two plastic films and the second on copper wire. These materials were tested a t several speeds in the range of 1.3 to 130 m./min. (50 to 5000 in./min.). Preliminary conclusions and plans for future work are offered.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 11 (1967), S. 2079-2079 
    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
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 10 (1966), S. 1659-1672 
    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: Solubility and spectroscopic evidence are presented to support the formation of A-B block copolymers between monomers undergoing anionic polymerization (A units) and monomeric formaldehyde (B units). Comonomers included in the study were styrene, methyl and n-butyl methacrylate, acrylonitrile, isoprene, and N, N-di-n-butylacrylamide. Similar evidence is presented on the formation of B-A-B copolymers between styrene and α-methylstyrene and formaldehyde; an A-(B-C) random copolymer of styrene, formaldehyde, and phenyl isocyanate (C) was also prepared. Experimental details for the preparation of high-purity, monomeric formaldehyde suitable for such work is described in some detail. It should be emphasized that this study was directed primarily toward showing the feasibility of preparing formaldehyde block copolymers; therefore, further work is needed to establish the quantitative nature of these reactions.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 11 (1967), S. 639-657 
    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 purpose of this paper is to show how a theoretical molecular weight distribution can be found which would result in a given gel permeation chromatogram. Also, to show how the method can be applied to blending problems where one desires a given molecular weight distribution.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 26 (1981), S. 4233-4245 
    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: Blends of polycarbonate and the copolyester based on 1,4-cyclohexanedimethanol and a mixture of terephthalic and isophthalic acids are known to be completely miscible. This study was concerned with various chemical events which may occur in this system, particularly during melt processing. Degradation reactions were studied by both TGA and dilute viscometry techniques, and some indications of component interaction were noted. The residual titanium catalyst from the copolyester formation was found to produce color formation by interaction with phenolic end groups in the polycarbonate and to promote interchange reactions. Both events could be suppressed by deactivation of the residual catalyst with appropriate additives. An indication of the extent of interchange reactions was obtained by following the crystallizability of the copolyester component using differential scanning calorimetry.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 48 (1960), S. 17-25 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Promoted preformed solids catalyze polymerization of ethylene and propylene and formation of copolymers of ethylene with such olefins as propylene and butene-1. The structure of the copolymers helps explain how they are formed and their properties. Kinetic studies alone do not distinguish between polymerization mechanisms involving either anionic centers or ion-radicals. Structural studies of ethylene-propylene copolymers of low propylene content show that they contain isolated propylene units in accord with the ion-radical theory of polymerization in a chemisorbed layer. Isolated short sidechains, so introduced, reduce density and increase flexibility. They give copolymers with flow properties more like those of linear polyethylenes than those of branched polyethylenes with long sidechains. Furthermore, they interfere with recrystallization and crystal growth; the resulting polymers have better stress-crack resistance and form clearer films.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 61 (1962), S. 39-44 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Copolymers of ethylene and C14-labeled propylene were prepared with a metal-oxide catalyst which polymerizes ethylene to a high density polymer. Methyl branches arising from the propylene were counted radiochemically and then related to the infrared absorption of films at 8.7 μ. This band was then used independently to determine methyl branching of a series of ethylene-propylene copolymers that differed in density and stiffness. Both properties decrease in value with an increase in branching.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 59 (1962), S. S45 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...