BIODEGRADABLE POLYESTER FIBER HAVING EXCELLENT THERMAL STABILITY AND STRENGTH, AND METHOD FOR PRODUCING SAME

摘要

An objective of the present invention is to provide a biodegradable polyester fiber which has excellent thermal stability and excellent fiber strength. Another objective of the present invention is to provide a method for producing a biodegradable polyester fiber which has excellent mechanical properties, especially excellent thermal stability. The present invention relates to a biodegradable polyester fiber which is composed of a poly(3-hydroxybutylate-co-3-hydroxyhexanoate) that has a 3HH molar fraction of 2-9% by mole. The present invention also relates to a method for producing the biodegradable polyester fiber, which is characterized by comprising a fiber formation step wherein a poly(3-hydroxybutylate-co-3-hydroxyhexanoate) is formed into fibers at a temperature that is not less than the glass transition temperature of the poly(3-hydroxybutylate-co-3-hydroxyhexanoate) but not more than 70°C during the melt extrusion of the poly(3-hydroxybutylate-co-3-hydroxyhexanoate).