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Thermal Degradation of Poly (Vinyl Acetate)

المؤلف:  A. Ravve

المصدر:  Principles of Polymer Chemistry

الجزء والصفحة:  652

2026-03-02

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Thermal Degradation of Poly (Vinyl Acetate)

Thermal decomposition of poly (vinyl acetate) results in a loss of acetic acid. The reaction is typical of thermal cleavages of esters. It is facilitated by formation of pseudo six-membered rings as a result of interactions between the b-hydrogens of the alcohol residues and the carboxylic groups:

When double bonds form, adjacent methylene groups become activated. The loss of acetic acid is the main product at temperatures up to 200–250C. Beyond these temperatures, aromatic pyrolytic compounds form. Studies of thermal degradation of copolymers of vinyl chloride with vinyl acetate showed that the copolymers are thermally less stable than the homopolymers [502, 503]. The ratio of hydrochloric acid to that of acetic acid that volatilize remains constant during the degradation. This indicates that neither is evolved preferentially, once the reaction begins [502, 503]. It is interesting to note that degradation studies of a copolymer of vinyl chloride and styrene also demonstrated that the copolymer is less stable than each of the homopolymers [504].