Fiber spinning behavior of a 3-hydroxybutyrate/3-hydroxyhexanoate copolymer

The fiber spinning behavior of a poly(3-hydroxyalkanoate) (PHA) copolymer resin containing 11.3 mol% hexanoate copolymer (H11) was studied to determine its usefulness in fiber based applications, such as nonwovens. Monocomponent fibers were spun initially, but it was found they would not solidify in the spinline. Bicomponent (sheath/core) fibers were melt spun using a H11 core and a polylactic acid (PLA), as well as a polyethylene succinate (PES) sheath. The spinning results showed that H11 levels up to 30wt% could be incorporated with stable spinning. The incorporation of H11 was found to be limited due to the slow crystallization kinetics of the H11 in the spinline. The neat and bicomoponent fibers were found to have tensile strengths similar to polypropylene. The PES based fiber compositions were found to have elongation-at-break values similar to PP. Neat H11 copolymer fibers were found to be readily biodegradable at 25°C under aerobic conditions.