Systematic investigations on the biological degradability of packing material II. On the biodegradability of polyvinylalcohol based films [German]

摘要

Earlier investigations have shown that polymers with a high density of functional groups along and/or in the molecular chain are more prone to good biodegradability than polymers with simple C-C-chains or blockpolymers with such "biologically hard" segments [1, 2]. In this context, biodegradability supporting functional groups should not only be susceptible to simple removal (as e.g. the decarboxylation of COO- groups), but also be attractive to enzymatic attack leading to chain fission by biochemical standard reactions or similar mechanisms. For the production of packing films with good mechanical properties and good biodegradablity, polymers like polyvinylalkohol and its derivatives seem to have the most encouraging properties among the water soluble films, ploy-epsilon-caprolactone and its derivatives being one of the most promising candidates for water insoluble films. Two mechanisms for the biodegradation of polyvinylalcohols-each dominating under different conditions and for different product types-are proposed. [References: 17]