Polydactic acid , biodegradability

T.Ochi, Y. Maeda, and H. Ohme, Polymer alloy fibers with good biodegradability and abrasion resistance consisting of blends comprising polydactic acid) and polyacetals, Japanese patent JP 2003227037 A2, assigned to Toray Industries, Inc., Japan, August 15, 2003. 

Blending of starch with aliphatic polyesters improves their processability and biodegradability Particularly suitable polyesters are poly(s caprolactone) and its copolymers, or polymers of higher melting point formed by the reaction of 1,4-butandiol with succinic acid or with sebacic acid, azelaic acid, or polydactic acid), poly(hydroxyalkanoates), and aliphatic-aromatic polyesters. 

There are exceptions to the rule that high polymers, including plastics, are resistant to biodegradation. Synthetic aliphatic polyesters such as polycaprolactone, polydactic acid) or its copolymers, poly(vinyl alcohol). 

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