Toughened polylactic acid fibers

• Main Authors: Eby, Tom, Zhou, Peiguang, Wideman, Gregory J, Topolkaraev, Vasily A, McEneany, Ryan J
• Format: Patent
• Language: English
• Published: 25.08.2020
• Subjects: APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBONFILAMENTS; BRAIDING; CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS,THREADS, FIBRES, BRISTLES OR RIBBONS; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; COTTON-WOOL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS,NON-WOVEN FABRICS; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; KNITTING; LACE-MAKING; MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARYMATERIAL; METALLURGY; NATURAL OR ARTIFICIAL THREADS OR FIBRES; NON-WOVEN FABRICS; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; SPINNING; TEXTILES; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; TRIMMINGS; WADDING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

Polylactic acid fibers formed from a thermoplastic composition that contains polylactic acid and a polymeric toughening additive are provided. The present inventors have discovered that the specific nature of the components and process by which they are blended may be carefully controlled to achieve a composition having desirable morphological features. More particularly, the toughening additive can be dispersed as discrete physical domains within a continuous phase of the polylactic acid. These domains have a particular size, shape, and distribution such that upon fiber drawing, they absorb energy and become elongated. This allows the resulting composition to exhibit a more pliable and softer behavior than the otherwise rigid polylactic acid. Through selective control over the components and method employed, the present inventors have discovered that the resulting fibers may thus exhibit good mechanical properties, both during and after melt spinning.