Japan Science and Technology Agency

Riken Corporation

Kaneka Corporation

Hideki Yamane

Yoshiharu Doi

Tadahisa Iwata

The present invention is a process for producing a fiber, comprising: melt-extruding polyhydroxyalkanoic acid; solidifying the polyhydroxyalkanoic acid by quenching it to its glass transition temperature +15&#xb0; C. or less, to form an amorphous fiber; cold-drawing the amorphous fiber at its glass transition temperature +20&#xb0; C. or less; and subjecting the fiber to heat treatment under tension. The present invention can provide: a process for producing a fiber with high strength, and the fiber produced through the process; and a process for producing a fiber with high strength and high modulus of elasticity and the fiber with high strength and high modulus of elasticity produced through the process, regardless of molecular weights of PHAs varying depending on origins such as a wild type PHAs-producing microorganism product, a genetically modified product, and a chemical product.

Polyhydroxyalkanoic acid fibers with high strength, fibers with high strength and high modulus of elasticity, and processes for producing the same

The object of the present invention is to provide melt-extrusion conditions and drawing process which enable to carry out stable and smooth fiber spinning of polyester produced by microorganisms, particularly P(3HB-CO-3HH) which conventionally had problems in spinning stability, as well as P(3HB) and P(3HB-CO-3HV). Another object of the present invention is to obtain filament having particular properties according to the process. The process comprises extruding a thermoplastic polymer from a melt-extruder, then rapidly cooling the same to at most the glass transition point of the polymer immediately after the extrusion to prevent the filament from blocking, and carrying out partial crystallization of the same rapidly at not less than the glass transition point.

Growing community of inventors

Moriyama, Japan

Hideki Yamane