초록 ▼

Biodegradable thermoplastic polymer blend compositions are presented in which a first polymer and a second polymer are intimately associated together in a uniform, substantially homogeneous blend. The second polymer of the composition acts to facilitate biodegradation of the composition, and of shap

Biodegradable thermoplastic polymer blend compositions are presented in which a first polymer and a second polymer are intimately associated together in a uniform, substantially homogeneous blend. The second polymer of the composition acts to facilitate biodegradation of the composition, and of shaped articles manufactured therefrom, at a rate which is enhanced over that of the most slowly biodegrading individual polymer component of the composition. The composition may further comprise a polysaccharide component, such as a starch component like destructurized starch.

대표청구항 ▼

[ What is claimed is:] [1.] A biodegradable thermoplastic polymer blend composition suitable for use in the manufacture of shaped articles comprisingat least one first polymer, wherein the first polymer is obtained by the co-polymerization of vinyl acetate and an alkene, with subsequent hydrolysis o

[ What is claimed is:] [1.] A biodegradable thermoplastic polymer blend composition suitable for use in the manufacture of shaped articles comprisingat least one first polymer, wherein the first polymer is obtained by the co-polymerization of vinyl acetate and an alkene, with subsequent hydrolysis of all or substantially all of the vinyl ester groups to form vinyl alcohol groups and wherein the molar ratio of vinyl alcohol units to alkene units is within the range of from about 80:20 to about 50:50, andat least one second polymer, wherein the second polymer is polyvinyl alcohol which has been partially converted from polyvinyl acetate, with a degree of hydrolysis of within the range of from about 71% to about 98%,wherein the rate at which the second polymer biodegrades is greater than the rate at which the first polymer biodegrades, wherein the first polymer and the second polymer are processed in intimate association to form a uniform, substantially homogeneous blend composition, whereupon cooling the blend composition, co-continuous phases of the first polymer and of the second polymer may be observed and essentially all of the co-continuous phase of either of the polymers is extractable from the blend composition, and wherein when the blend composition is subjected to conditions favorable for biodegradation, the rate at which the first polymer biodegrades is enhanced by the second polymer.