Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Physics  (2)
  • Chemistry  (1)
  • Physical Chemistry  (1)
  • 1
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 14 (1976), S. 701-711 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The G values of poly(methyl methacrylates) (PMMA), polycarbonates, and a polylactone for γ-radiation were determined by using a computer-assisted GPC as the primary tool for the measurement of the number-average molecular weights M̄n. The accuracy and precision of the automated GPC were found to have a normalized standard deviation (σ/M̄n) of less than 7%. The G value of PMMA was determined to be essentially independent of molecular weight. For low molecular weight polymers, some nonlinearity in the I/M̄n versus dosage plot was observed at low dosage, i.e., about 1 Mrad.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 169-177 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of methyl methacrylate (MMA)-methacrylic acid (MAA) copolymers containing up to 50% methacrylic acid and the respective homopolymers were reproducibly pyrolyzed at 900°C and the fragments identified by gas chromatography (GC) or GC-mass spectroscopy. It was shown that PMMA and the MMA portions of blocky or random copolymers yielded 99% MMA, while a large portion (50-60%) of the MAA broke down to give a wide variety of hydrocarbons via decarboxylation and/or anhydride formation. Both unsaturated aliphatic and aromatic hydrocarbons, as well as the minor products of the MMA decomposition, support free-radical processes for these decompositions. It was also shown that the copolymers readily complex oxygenated solvents (which did not affect decomposition) and metal ions (which markedly affected the products).
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 28 (1996), S. 43-55 
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions between F2 and the lowest members of the homologous series of perfluoroalkyl iodides (CF3I, C2F5I, and n-C3F7I) have been studied. For these compounds, an exponential decrease in the alkyl iodide concentration over time following an induction period is observed for certain experimental conditions. Other conditions lead to chaotic-like kinetic behavior where the rate of alkyl iodide consumption continually changes. Kinetic rate data with CF3I show that the disappearance rate depends upon both the type of surface and surface preparation. For all three compounds, Arrhenius plots reveal activation energies on the order of 10 kcal/mol, consistent with effective initiation steps of F2 + RI → RIF + F, where R represents the CF3, C2F5, or n-C3F7 radical respectively. The end products of the F2 + RI reactions are RF, R2, and IF5, suggesting that the R radicals play an important kinetic role. Introducing O2 into the F2 + RI reaction systems results in successive oxidation of R by O2, leading to the formation of CF2O as an additional end product. IF(B → X) emission is observed from the RI-rich F2 + RI reactions, confirming the existence of IF as an intermediate. © 1996 John Wiley & Sons, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...