Kyoto Institute of Technology

Other

Teijin Limited

Takasago International Corporation

Mitsubishi Kasei Corporation

Mitsui Toatsu Chemicals, Incorporated

Kyowa Hakko Kogyo Co., Ltd.

Ono Pharmaceutical Co., Ltd.

New Japan Chemical Co., Ltd.

Research Development Corporation

Musashino Chemical Laboratory, Ltd.

Mutual Corporation

Yoshiharu Kimura

Hideki Yamane

Kohei Oda

Kiyotsuna Toyohara

Toshio Kitao

Koichi Hashimoto

Yoji Hori

Yasuhito Maeda

Hosei Shinoda

Hiroyoshi Minematsu

Yorozu Yokomori

Akio Nishiura

Shuh Narumiya

Toshikazu Murayama

Osamu Hayaishi

Naoki Ikeda

Ryuji Nonokawa

Masafumi Yoshimura

Shin To

Soonih Kim

Yuka Komazawa

Kazuaki Mizoguchi

Zhen Tang

Nobuko Tsuzaki

Tsuyoshi Aoki

Midori Ikegame

Norio Yanagisawa

Yamamoto, Kenji

Taniguchi, Isoji

Masami Tsuboshima

Kazuki Fukushima

Kazumi Hiraga

Masayuki Takada

Hiroki Nakata

Daisuke Masaki

It is an object of the present invention to provide polylactic acid containing a stereocomplex crystal and having excellent moldability, a high molecular weight, high crystallinity and a high melting point and a process for manufacturing the same. It is another object of the present invention to provide a composition comprising the polylactic acid and a molded product of the polylactic acid. The present invention is characterized from polylactic acid having a weight average molecular weight of 80,000 to 500,000 and a melting peak at 195&#xb0; C. or higher which accounts for 80% or more of the total of melting peaks in the temperature elevation step when measured by a differential scanning calorimeter (DSC) and a process for manufacturing the same.

Polylactic acid and manufacturing process thereof

It is an object of the present invention to produce a polylactic acid having a high molecular weight such as a weight average molecular weight (Mw) of more than 100,000 from which only a stereocomplex crystal is grown even by repeating melting and crystallization. The present invention is a process of producing a polylactic acid, including the steps of:

Process of producing polylactic acid

A microorganism which belongs to the genusand has the ability of degrading an aromatic polyester, and a method of degrading an aromatic polyester by using the microorganism. According to this method, the aromatic polyester can be degraded safely and relatively swiftly at a low cost.

Microorganism capable of degrading aromatic polyester and method of degrading aromatic polyester using the same

A polyester containing aromatic moieties is contacted with microorganisms having the activity of decomposing the polyester to decompose or reduce it. Preferably, either or both ofFERM BP-6445 orFERM BP-6444 was contacted with the polyester to decompose or reduce it. A fiber made of the polyester or a cloth made of such fiber may be reduced by contacting it with the microorganisms having the activity of decomposing the polyester.

Method for decomposing polyesters containing aromatic moieties, a denier reduction method of fiber, and microorganism having activity of decomposing the polyester

Method for decomposing polyesters containing aromatic moieties, a denier reduction method of fiber, and microorganisms having activity of decomposing the polyester

A biodegradable complex fiber which retains excellent biodegradability and hydrolyzability and has high strength and high melting temperature suitable for practical use and a method for producing the biodegradable complex fiber are provided. The biodegradable complex fiber comprises at least one polymer material selected from the group consisting of a polyglycolic acid, a poly(glycolic acid-co-lactic acid) and polylactic acid as a core component or as a shell component and a polymer material of poly(3-hydroxybutyric acid) groups or a polymer material of an aliphatic polyester consisting of a dibasic acid and a diol as a shell component or as a core component. The method comprises producing the biodegradable complex fiber by melt spinning.

Biodegradable complex fiber and method for producing the same

A polyester containing aromatic moieties is contacted with microorganisms having the activity of decomposing the polyester to decompose or reduce it. Preferably, either or both of Trichosporon FERM BP-6445 or Arthrobacter FERM BP-6444 was contacted with the polyester to decompose or reduce it. A fiber made of the polyester or a cloth made of such fiber may be reduced by contacting it with the microorganisms having the activity of decomposing the polyester.

A polyester fiber is provided, which does not produce a huge amount of residues during its reducing process, and shows good appearance, feeling and superior characteristics as a fiber, such as a high tensile strength and elongation. Such polyester fiber is a conjugate fiber comprising a core spinned from a polyester containing an aromatic moiety and a skin layer surrounding the core, the skin layer spinned from an aliphatic polyester. The skin layer may be easily reduced by contacting it with an alkaline solution or an enzyme, to provide a reduced fiber with good appearance, feeling and superior characteristics as a fiber.

Conjugate fibers and manufacturing method of the same

The present invention provides a process for producing polyhydroxycarboxylic acids which have a weight-average molecular weight of 50,000 or above and which are excellent as biodegradable plastics by polycondensing hydroxycarboxylic acids or oligomers thereof in the presence of an inorganic solid acid catalyst in combination with an alkali metal or an alkaline earth metal.

Process for producing polyhydroxycarboxylic acid

Disclosed are a process for producing a porous stretched article of .beta.-crystalline polypropylene-based resin, the process comprising the steps of crystallizing a melt of a polypropylene-based resin composition at a temperature of 15.degree. to 140.degree. C. to form a solidified product containing .beta.-form crystals and stretching the resulting solidified product at a temprature which is higher than 20.degree. C. but lower than the melting point of the .beta.-form crystals in said solidified product, the polypropylene-based resin composition comprising a polypropylene-based resin and 0.0001 to 5 parts by weight, per 100 parts by weight of the polypropylene-based resin, of at least one specific amide compound; and a porous stretched article produced by the process.

Porous stretched article of polypropylene-based resin and process for

A process for producing a biodegradable polymer, which comprises subjecting a cyclic compound of the following formula (1) or (2) to ring opening polymerization: ##STR1## wherein R.sub.1 is a C.sub.1-10 alkyl group, ##STR2## wherein R.sub.2 is a C.sub.1-10 alkyl group, and R.sub.3 is a hydrogen atom or a C.sub.1-10 alkyl group.

Process for producing a biodegradable polymer

The present invention provides a nylon composition having increased hydrolyzability which is obtained by physically mixing 100 parts by weight of a nylon with 1 to 50 parts by weight of at least one polymer selected from the group consisting of polylactic acid, polyglycolic acid and a copolymer containing 50 mol % or more of a lactic acid unit or a glycolic acid unit as a repeating unit in its chain; and a method for increasing the hydrolyzability of a nylon by preparing such a composition. High hydrolyzability can be imparted to the nylon inherently having extremely low hydrolyzability without impairing its original mechanical strength. Therefore, various molded articles made from the nylon can be hydrolyzed under natural circumstances, and thus the wastes are not stored.

Nylon composition having increased hydrolyzability and method for

A polyurethane (I) of 1000 to 100,000 in average molecular weight, comprising plural segments, which are each structural units of A-B, A-C and A-D of the formulae: ##STR1## the proportion of the said segments of A-B, A-C and A-D, i.e. x:y:z is in the molar ratio 0.01 to 0.8:0 to 0.80:0 to 0.99, provided that the sum of x, y and z is 1.0; each segment being produced by combining with repeat units of A, B, C and D of the formulae: ##STR2## wherein R.sup.1 is a skeleton of a diisocyanate and the three R.sup.1 's in each of segments A-B, A-C and A-D can be the same or different; aza is a group of the formula: ##STR3## wherein Y.sup.1 and Y.sup.2 which can be the same or different, are oxygen, imino(--NH--) or a group of the formula:

Azo containing polyurethanes for drug delivery to the large intestines

An electrically conductive alumina fiber which heretofore known only as electrically insulative is now provided, which comprises an aluminum oxide matrix, and a continuous phase of carbon in the aluminum oxide matrix, the continuous phase of carbon affording an electrically conductive property to the fiber. Also, a method of producing the alumina fiber is disclosed, comprising pyrolyzing a fiber of poly[(acyloxy)aloxane] having a formula ##STR1## wherein, R.sub.1 represents CH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.3, R.sub.2 represents ##STR2## or other substituted aromatic group, in an inert atmosphere.

Alumina fiber with carbon inclusion and a method of producing the same

Growing community of inventors

Omihachiman, Japan

Yoshiharu Kimura