Natureworks LLC

Robert A Green

Jeffrey John Kolstad

Christopher M Ryan

Jed Richard Randall

Chad Henry Kamann

James Russell Valentine

Donavon Kirschbaum

Polylactide fibers are made from a blend of polylactides. One of the polylactides has a ratio of R-lactic and S-lactic units from 8:92 to 92:8. The second polylactide has a ratio of the R-lactic and S-lactic units of &#x2265;97:3 or &#x2264;3:97. The ratio of the R-lactic units to S-lactic units in the blend is from 7:93 to 25:75 or from 75:25 to 93:7. The polylactide fiber contains at least 5 Joules of polylactide crystallites per gram of polylactide resin in the fiber.

Polylactide fibers

Polylactide fibers are made from a blend of polylactides. One of the polylactides has a ratio of R-lactic and S-lactic units from 8:92 to 92:8. The second polylactide has a ratio of the R-lactic and S-lactic units of &#x3e;97:3 or &#x3c;3:97. The ratio of the R-lactic units to S-lactic units in the blend is from 7:93 to 25:75 or from 75:25 to 93:7. The polylactide fiber contains at least 5 Joules of polylactide crystallites per gram of polylactide resin in the fiber.

Conjugate fibers are prepared in which at least one segment is a mixture of a high-D PLA resin and a high-L PLA resin. These segments have crystallites having a crystalline melting temperature of at least 200&#xb0; C. At least one other segment is a high-D PLA resin or a high-L PLA resin. The conjugate fibers may be, for example, bicomponent, multi-component, islands-in-the-sea or sheath-and-core types. Specialty fibers of various types can be made through further downstream processing of these conjugate fibers.

Process of making conjugate fibers

PLA stereocomplex fibers are made by separately melting a high-D PLA starting resin and a high-L starting resin, mixing the melts and spinning the molten mixture. Subsequent heat treatment introduces high-melting 'stereocomplex' crystallinity into the fibers. The process can form fibers having a high content of 'stereocomplex' crystallites that have a high melting temperature. As a result, the fibers have excellent thermal resistance. The process is also easily adaptable to commercial melt spinning operations.

Growing community of inventors

Raleigh, NC, United States of America

Robert A Green