ISSN:
0323-7648
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Description / Table of Contents:
The electron donor-acceptor (EDA) complex formation constant Kx (related to molar fractions) as determined by UV spectroscopy at 25°C in cyclohexane were found to be 1.0 with acrylonitrile-styrene, 0.5 with methacrylonitrile-styrene, 1.1 with acrylonitrile-α-methylstyrene and 1.1 with methacrylonitrile-α-methycrylonitrile-α-methylstyrene. The values of the enthalpy of complex formation decrease in the series of comonomer systems indicated, thus the stability of the complexes being affected by steric effects. Considerations on the participation of EDA complexes in the propagation step of the acrylonitrile-styrene bulk copolymerization can be based on the concentration ratios of the complexes.
Notes:
Die UV-spektroskopisch bei 25°C in Cyclohexan bestimmten Elektronendonator-Akzeptor(EDA)-Komplexbildungs-konstanten Kx (bezogen auf Molenbrüche) betragen für Acrylnitril-Styrol 1,0, Methacrylnitril-Styrol 0,5, Acrylnitril-α-Methylstyrol 1,1 und Methacrylnitril-α-Methylstyrol 1,1. Die Komplexbidungsenthalpien nehmen in der angegebenen Reihe der Comonomersysteme ab; demnach beeinflussen sterische Effekte die Komplexstabilität. Die Beteiligung von EDA-Komplexen am Wachstumsschritt der Acrylnitril-Styrol-Copolymerisation in Substanz kann auf Basis der Komplexkonzentrationsverhältnisse in Betracht gezogen werden.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/actp.1979.010300509
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