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 comonomer species and concentration on the ease of alkaline hydrolysis of vinyl acetate copolymers in the aqueous dispersion form is reported. The comonomers studied include higher vinyl esters, acrylic esters, a fumaric diester, and ethylene. The significance of the emulsion polymerization formulation has also been considered. The rate of hydrolysis is reduced with increasing proportions of comonomers and with increasing length and branching of the alkyl side chain originating from such comonomers. Branched long-chain tertiary vinyl esters reduce not only the rate but also the extent of hydrolysis, being resistant to hydrolysis themselves and also protecting part of the more susceptible vinyl acetate; inhomogeneous copolymers, specially prepared, were less resistant than the more homogeneous copolymer of the same overall composition. The inclusion of quite small amounts, such as 1% by weight, of acid comonomers has a relatively large effect, increasing ease of hydrolysis. For comparison, the behavior of higher vinyl ester homopolymers and methyl methacrylate copolymers with acrylic esters is included. It is concluded that the major factors influencing ease of hydrolysis are steric and other environmental effects arising from the copolymer microstructure.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1968.070120106
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