ISSN:
0193-7197
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Because of the prominence of vinylidene chloride/methyl acrylate copolymers in barrier plastic packing applications, the degradation of these materials continues to be the focus of much interest. The prominent degradation process at moderate temperature (〈200°C) is dehydrochlorination. This reaction is a typical radical chain process with distinct initiation, propagation, and termination phases. A principal defect structure responsible for the initiation of degradation is unsaturation along the polymer backbone. Although most stabilization packages for these polymers contain basic components to absorb hydrogen chloride as it is generated, materials sufficiently basic to abstract hydrogen chloride might actually enhance the rate of degradation by introducing double bonds into the polymer structure. That this is the case has been established by the thermogravimetric examination of the degradation of a methyl acrylate (5 mol%)/ vinylidene chloride copolymer in the presence of amines of varying base strengths. In general, the initiation rate constant, kt, for the degradation process is enhanced in the presence of amine.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/vnl.730130405
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