Patent ID: 8936740
Filing Date: 2015-01-20
Classification: B29C,B29K,C08G,C08L,D01D,D01F,D04H,Y10T

Abstract:
1. A method for forming a polylactic acid fiber, the method comprising; melt blending a polylactic acid with a polyepoxide modifier and a polymeric toughening additive to form a thermoplastic composition, wherein the melt blending occurs at a temperature above the melting point of the polylactic acid and below a temperature of about 230° C., the polyepoxide modifier having a number average molecular weight of from about 15,000 to about 250,000 grams per mole, wherein the amount of the polyepoxide modifier is from about 0.01 wt. % to about 10 wt. %, based on the weight of the polylactic acid, and the polymeric toughening additive comprises an ethylene/α-olefin copolymer, propylene/α-olefin copolymer, or a combination thereof; thereafter, extruding the thermoplastic composition at a temperature above about 230° C. to facilitate reaction of the polyepoxide modifier with the polylactic acid; and passing the reacted composition through a die to form a fiber, wherein the melt blended composition comprises a plurality of discrete domains dispersed within a continuous phase, the discrete domains containing the polyepoxide modifier and the polymeric toughening additive and the continuous phase containing polylactic acid.