Weight loss poly degradation

Viscosity Loss Vith Tine. Poly(l-amidoethylene) solutions lose viscosity with time(5l). Several authors have attributed this viscosity loss to oxygen or radical degradation of the polymer(5l), but Francois(52) has shown that changes in viscosity only occur in solutions made from broad-molecular-weight-distribution poly( 1-amidoethylene). Since very... 

PVA films buried in soil were tested after 120 days and showed only very limited signs of biodegradation, and even field tests with PVA sheets buried for 2 years in different natural soil sites showed only limited (10%) weight loss. No traces of colonising microorganisms were detected on the incubated material. Degradable polymers like poly(hydroxy butyrate), PCL or starch are usually extensively... 

Milled rigid sheets of poly (vinyl chloride) on heating at 185°C. lose weight at a rate which increases with time. By polymer fractionation procedures, it was shown the rate of hydrogen chloride loss increases as the content of tetrahydro-furan-insoluble resin increases. The insoluble resin content accumulates at a rate which depends, in part, on the additive present. This insolubilization reaction is catalyzed by cadmium compounds. The increased dehydrochlorination rate of the insoluble crosslinked resins may result from the susceptibility of the crosslinked structures to oxidation and from the subsequent thermal degradation of the oxidation products. The effects of various common additives on the rates of insolubilization and weight loss are described. 

Fig. 5 Degradation profiles (percent weight loss) of compression-molded poly[bis(p-carboxyphenoxy) propane anhydride] (PCPP) containing varying ratios of sebacic acid (SA). The copolymers were incubated in 0.1 M pH 7.4 phosphate buffer at 3TC. (From Ref. l)...

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