Abstract: An object of the present invention is to provide a method for producing a polymeric molded product, which does not undergo a considerable molecular weight reduction during melt-molding, even in a polymer may easily lose its molecular weight when it is in a melted state. The present invention provides a method for producing a polymeric molded product, which comprises melt-molding a polymer comprising lamellar crystals that are different in lamella thickness, in a temperature range where some of the lamellar crystals undergo melting and flowing, and the other balance lamellar crystals remain unmelted.

Abstract: An object of the present invention is to provide a method for producing a polymeric molded product, the method enabling expansion of a temperature range that can be used for partial melting. The present invention provides a method for producing a polymeric molded product, which comprises subjecting a crystalline polyhydroxyalkanoate to a heating treatment at a temperature equal to or higher than a glass transition temperature; and melt-molding a polyhydroxyalkanoate yielded by the heating treatment, which comprises lamellar crystals that are different in lamellar thickness, in a temperature range where some of the lamellar crystals undergo melting and flowing, and the other balance lamellar crystals remain unmelted.

Abstract: An object of the present invention is to provide a stretchable polyester having shape followability and flexibility by elastic response and being able to suppress deterioration over time due to secondary crystallization. The present invention provides a stretchable polyester which is an aliphatic copolymer polyester containing two or more types of monomer units, wherein the stretchable polyester contains an ?-form and an amorphous structure, and a degree of orientation determined by X-ray of the ?-form is 50% or greater.

Abstract: The present invention relates to a high molecular weight polymer having an aldaric acid as a constitutional unit, and a method for producing the same, and more specifically, relates to a thermoplastic polymer which comprises at least one repeating unit derived from an aldaric acid, and has a weight average molecular weight of 3,800 or more.

Abstract: The present invention relates to a high molecular weight polymer having an aldaric acid as a constitutional unit, and a method for producing the same, and more specifically, relates to a thermoplastic polymer which comprises at least one repeating unit derived from an aldaric acid, and has a weight average molecular weight of 3,800 or more.

Abstract: A method for producing a polypropylene fiber, which can produce a high strength polypropylene fiber without using a special raw material and/or means is provided. The method for producing a polypropylene fiber includes the step of spinning a melt extruded fiber, the step of keeping cold, and the step of drawing, in which a ratio of a take-off speed with respect to an extrusion speed in the step of spinning the melt-extruded fiber is 50 to 750.

Abstract: A method for producing a polypropylene fiber, which can produce a high strength polypropylene fiber without using a special raw material and/or means is provided. The method for producing a polypropylene fiber includes the step of spinning a melt extruded fiber, the step of keeping cold, and the step of drawing, in which a ratio of a take-off speed with respect to an extrusion speed in the step of spinning the melt-extruded fiber is 50 to 750.

Abstract: The present invention aims to provide biodegradable polyester fibers excellent in thermal stability and fiber strength. Another aim is to provide a method for producing biodegradable polyester fibers excellent in mechanical properties, particularly in thermal stability. The present invention relates to biodegradable polyester fibers comprising a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) that has a 3HH molar fraction of 2 to 9 mol %. The present invention also relates to a method for producing the biodegradable polyester fibers, comprising a fiber forming step of melt-extruding a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) to form fibers at a temperature higher than or equal to the glass transition temperature of the poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) but not higher than 70° C.

Abstract: An object of the present invention is to provide: a process for conveniently producing a fiber with high strength, regardless of molecular weight polymer composition, or the like of PHAs, which vary depending on origins such as a wild-type PHAs-producing microorganism product, a genetically modified strain product, and a chemical product; and the fiber with high strength produced through the process. The present invention provides: a process for producing a fiber, comprising: melt-extruding polyhydroxyalkanoic acid to form a melt-extruded fiber; rapidly quenching the melt-extruded fiber to the glass transition temperature of polyhydroxyalkanoic acid +15° C. or less, and solidifying the fiber to form an amorphous fiber; forming a crystalline fiber by leaving the amorphous fiber to stand at the glass transition temperature +15° C. or less; drawing the crystalline fiber; and further subjecting the crystalline fiber to stretch heat treatment.

Abstract: 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° C. or less, to form an amorphous fiber; cold-drawing the amorphous fiber at its glass transition temperature +20° 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.

Abstract: An object of the present invention is to provide products composed of a biodegradable raw material(s). The present invention provides a biodegradable oil absorbing film containing polyhydroxyalkanoate.

Abstract: An object of the present invention is to provide: a process for conveniently producing a fiber with high strength, regardless of molecular weight polymer composition, or the like of PHAs, which vary depending on origins such as a wild-type PHAs-producing microorganism product, a genetically modified strain product, and a chemical product; and the fiber with high strength produced through the process. The present invention provides: a process for producing a fiber, comprising: melt-extruding polyhydroxyalkanoic acid to form a melt-extruded fiber; rapidly quenching the melt-extruded fiber to the glass transition temperature of polyhydroxyalkanoic acid +15° C. or less, and solidifying the fiber to form an amorphous fiber; forming a crystalline fiber by leaving the amorphous fiber to stand at the glass transition temperature +15° C. or less; drawing the crystalline fiber; and further subjecting the crystalline fiber to stretch heat treatment.

Abstract: 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° C. or less, to form an amorphous fiber; cold-drawing the amorphous fiber at its glass transition temperature +20° 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.

Abstract: 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° C. or less, to form an amorphous fiber; cold-drawing the amorphous fiber at its glass transition temperature +20° 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 PEAs-producing microorganism product, a genetically modified product, and a chemical product.

Abstract: The present invention relates to a process for producing a film of polyhydroxyalkanoic acid, comprising: partially melting and hot drawing an unoriented polyhydroxyalkanoic acid film; and further drawing the obtained hot-drawn film to obtain a two-stage drawn film. The present invention provides a PHA film having sufficient strength and flexibility, and having biodegradability and biocompatibility, and a process for producing the film easily and with good reproducibility.

Abstract: 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° C. or less, to form an amorphous fiber; cold-drawing the amorphous fiber at its glass transition temperature +20° 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.

Abstract: Poly(3-hydroxybutanoic acid) having a number average molecular weight of not less than 500,000 is oriented at a draw ratio of 2-fold or more to reproducibly obtain a film made of poly(3-hydroxybutanoic acid) having biodegradability and biocompatibility as well as sufficient strength and flexibility (for example, tensile strength of not less than 30 MPa and elongation to break of not less than 15%).