Lactic Acid Based Compositions with Enhanced Properties

A crosslinked lactic acid polymer composition containing (i) a macromer comprising (i-a) a flexible segment produced by the condensation of two or more compounds selected from the group consisting of lactones, furans, epoxies, isocyanates, anhydrides, dianhydrides, alcohols, diols, triols, carboxylic acids, dicarboxylic acids, tricarboxylic acids, esters, diesters, triesters, ethers, diethers, and triethers; and (ii) a lactic acid polymer produced by the condensation of a lactic acid monomer or dimer selected from the group consisting of D-lactic acid, L-lactic acid, D,L-lactic acid, L,L-lactide, D,D-lactide, and D,L-lactide; wherein the macromer and the lactic acid polymer contain carbon-carbon single-bond crosslinks. The macromer may further contain (i-b) a lactic acid segment produced by the condensation of a lactic acid monomer or dimer selected from the group consisting of D-lactic acid, L-lactic acid, D,L-lactic acid, L,L-lactide, D,D-lactide, and D,L-lactide with a polyfunctional monomer selected from the group consisting of dianhydrides, diols, triols, dicarboxylic acids, and tricarboxylic acids. Also, a method of producing the crosslinked lactic acid polymer composition by (a) condensing two or more compounds selected from the group consisting of lactones, furans, epoxies, isocyanates, anhydrides, dianhydrides, alcohols, diols, triols, carboxylic acids, dicarboxylic acids, tricarboxylic acids, esters, diesters, triesters, ethers, diethers, and triethers, to yield a flexible segment of a macromer; and (b) melt blending the macromer with a lactic acid polymer, to yield the crosslinked lactic acid polymer. The method may further involve (c) condensing a lactic acid monomer or dimer selected from the group consisting of D-lactic acid, L-lactic acid, D,L-lactic acid, L,L-lactide, D,D-lactide, and D,L-lactide with a polyfunctional monomer selected from the group consisting of dianhydrides, diols, triols, dicarboxylic acids, and tricarboxylic acids, to yield a lactic acid segment; and (d) condensing the lactic acid segment and the flexible segment, to yield the macromer.