Mitsui Toatsu Chemicals, Incorporated

Mitsui Chemicals, Inc.

Ntn Corporation

A School Corporation Kansai University

Masanobu Ajioka

Akihiro Yamaguchi

Kazuhiko Suzuki

Chojiro Higuchi

Takayuki Watanabe

Yasuhiro Kitahara

Hiroshi Suizu

Masatoshi Takagi

Shinji Takenaka

Hiroyuki Itoh

Katashi Enomoto

Yuji Terado

Toshio Katoh

Taiji Kameoka

Takeshi Kashima

Masafumi Kataita

Akinori Nagatomo

Yoshitsugu Kono

Takeshi Oura

Hosei Shinoda

Shoji Obuchi

Hiroaki Tamatani

Shinji Ogawa

Masayuki Sakai

Shoji Hiraoka

Hiroyuki Suzuki

Tomoyuki Nakata

Yasushi Kotaki

Isao Kikuchi

Yoshitsugu Kohno

Ikumi Kitada

Keisuke Takuma

Tadamitsu Kiyoura

Yasuo Kogure

Shuhei Ikado

Kazuo Kanaya

Tokio Nagayama

Ryo Shinagawa

Nobuo Shiraishi

Masakazu Hirata

Akira Misawa

Ichiro Fujio

Shinichi Usugi

Takayuki Onogi

Takeharu Isaki

Mitsuo Kudoh

Toshihide Suzuki

Naoshi Fujimoto

Teruyuki Nagata

Masahiro Ohta

Yasunori Yoshida

Hideaki Oikawa

Hiroshi Kimura

Atsuo Otsuji

Hiroyuki Yamashita

Mitsunobu Yoshida

Tatsuhiro Urakami

Yoshiro Tajitsu

Wataru Yamashita

Ryuichi Mita

Yoshihiro Sakata

Kenichi Goto

Akio Karasawa

Isamu Ghoda

Akihiro Tamaki

Atsushi Shibuya

Rihoko Suzuki

Takeshi Karino

Tomomi Yoshimura

Toshihiro Motoshima

Makoto Aiga

Mari Kataoka

Tomoko Kamashita

Tatsuya Kawaguchi

Kazuhika Suzuki

Hisashi Aihara

Isamu Kawamura

Kimitaka Chida

Takaharu Isaki

Yoshiaki Aso

The invention provides a piezoelectric polymer material including a helical chiral polymer having a weight average molecular weight of from 50,000 to 1,000,000 and having optical activity, the piezoelectric polymer material having a piezoelectric constant dat 25&#xb0; C. of 10 pC/N or more, a degree of crystallinity obtained by X-ray diffraction of from 40% to 80%, and a haze of from 0.5 to 30.

Piezoelectric polymer material, process for producing same, and piezoelectric element

The invention relates to a process for producing an aliphatic polyester excellent in stability which includes subjecting an aliphatic polyester containing at least 50% of an aliphatic hydroxycarboxylic acid unit, obtainable by solid-phase polymerization under a flowing gas in the presence of a volatile catalyst so as to have a desired weight average molecular weight within the range of 50,000 to 1,000,000, to a heat treatment at a temperature equal to or higher than the reaction temperature of the solid-phase polymerization under a flowing gas with maintaining the aliphatic polyester in a solid state. According to the process of the invention, an aliphatic polyester excellent in stability at molding and storage stability is obtained.

Process for producing aliphatic polyester excellent in stability

An aliphatic polyester formed item having transparency and crystallinity in combination by crystallizing, in the course of or after processing, an aliphatic polyester composition comprising aliphatic polyester and one or more transparent nucleating agent selected from the group consisting of aliphatic carboxylic acid amide, aliphatic carboxylic acid salt, aliphatic alcohol and aliphatic carboxylic acid ester having a melting point of 40-300&deg; C.

Films and molded articles formed from aliphatic polyester compositions containing nucleating agents

A process for producing aliphatic polyester wherein a crystallized aliphatic polyester prepolymer formed from an aliphatic dihydric alcohol and an aliphatic dicarboxylic acid and having a weight-average molecular weight of 2,000 to 100,000 is caused to undergo solid-phase polymerization in the presence of a volatile catalyst to make an aliphatic polyester having a weight-average molecular weight of 50,000 to 1,000,000. This process is more efficient than any prior process calling for a complicated step for catalyst removal, since it enables the removal of the catalyst from the reaction system during and/or after solid-phase polymerization. The polyester is comparable in stability to any aliphatic polyester having any catalyst removed therefrom.

Process for preparing aliphatic polyester

Preparation process of the formed product of L-lactic acid base polymer

A polylactic acid-based resin composition composed of a high molecular ingredient (A) comprising polylactic acid (a1) and an aliphatic polyester (B), and a film, particularly an inflation film, prepared from the resin composition. The film comprising the polylactic acid-based resin composition of the invention is biodegradable and excellent in flexibility and resistance to blocking of film and bleeding-out of plasticizer, has no anisotropy in tear strength, and can be suitably used for an agricultural multi-film and garbage bag. When the film of the invention is used for food wrapping, the film prevents fungus growth and contamination of color or odor, and thus can be suitably used.

Polylactic acid resin composition and film therefrom

The invention provides a composite resin composition comprising aliphatic polyester resin (component A) having aliphatic hydroxycarboxylic acid units, one or more biomass material (component B) selected from the group consisting of cellulose, lignocellulose and starch and unsaturated carboxylic acid or a derivative thereof (component C), wherein the composite resin composition comprises a component obtained by covalently bonding a portion or the whole of component A and component B through component C. On processing into various formed items, the composite resin composition of the invention exhibits excellent tensile strength and other physical properties and processability and simultaneously has good biodegradability, and enable biomass materials of low added value to apply to high added value uses in a large amount.

Composite resin composition

The invention provides a process for producing high-molecular aliphatic polyesters capable of being substitutes for general-purpose resins that are required to have high toughness, in a simplified manner and at a high volume efficiency. Specifically, in the process, used as the starting material is an easily-available, low-molecular aliphatic polyester prepolymer to be prepared through polycondensation of inexpensive materials of an aliphatic hydroxycarboxylic acid such as lactic acid, glycolic acid or the like, an aliphatic polyalcohol such as butanediol or the like, and an aliphatic polycarboxylic acid such as succinic acid or the like, and the starting prepolymer is crystallized and thereafter polycondensed in a solid phase in the presence of a catalyst to give the intended, tough and high-molecular aliphatic polyester.

Preparation process of polyester

A lactic acid polymer composition comprising formulating 100 parts by weight of a mixture consisting of 80-95% by weight of an L-lactic acid polymer having an L-lactic acid proportion of 75% or more and 5-20% by weight of a plasticizer selected from the group consisting of a polyhydric alcohol ester and a hydroxypolycarboxylic acid ester, 0.1-5 parts by weight of an anti-blocking agent having a SiO.sub.2 content of 90% or more and an average particle size of 7-50 nm, and 0.1-2 parts by weight of a slip agent; a molded product and film obtained from the composition; and a preparation process of the same are disclosed. The molded product and film are excellent in processability, transparency, flexibility, anti-blocking property and slip, and can be degraded into harmless water and carbon dioxide under natural environment, when abandoned.

L-lactic acid polymer composition, molded product and film

A process for treating pyruvic acid and other impurities of lactic acid by reduction treatment of an aqueous lactic acid solution and for obtaining high quality lactic acid having a substantially no pyruvic acid content, high purity, excellent heat stability and improved smell. Further, a high molecular weight polylactic acid having low coloration and consistent quality can be prepared by dehydration polycondensation of lactic acid obtained by the reduction treatment.

Purification process of lactic acid

A degradable copolymer filament comprising an internal structure having the following separate phases: (a) a matrix phase comprised as a primary component of a polymer segment which exhibits a tensile Young's modulus of 2 GPa or less and a strength retention of 50% or more after two weeks in water at 37.degree. C., pH 7.3, and (b) a micro-dispersed phase comprised as a primary component of a polymer segment which exhibits a tensile strength of 200 MPa or more and a strength reduction greater than the matrix phase in water at 37.degree. C., pH 7.3. The weight ratio of each component in the matrix phase and dispersed phase is 50:50 to 95:5, respectively, and the dispersed phase a needle structure oriented by stretching in the fiber direction. A degradable monofilament having an excellent mechanical strength and flexibility, moderate hydrolyzability, high ligature stability and being suitable as a material of surgical absorbable suture can be obtained. A preparation process is also provided.

Degradable monofilament and preparation process thereof

A low-birefringent organic optical component comprising a polymer prepared by polymerizing a racemic mixture of the monomer with an asymmetric spiro ring represented by general formula (1) as an essential ingredient; wherein ring A represents a monocyclic or polycyclic organic group, wherein two ring As are mutually bound each other via a spiro bond to form a spiro ring which has a molecular asymmetric structure; n is an integer of 0 to 10; X.sub.1 and Y.sub.1 are binding groups; and Z.sub.1 is a polymerization-active group. The component has excellent transparency, mechanical strength and heat resistance, as well as a low birefringence.

Low-birefringent organic optical component and a spirobiindan polymer

A biodegradable aliphatic polyester elastomer which has rubber-like elasticity, hardness of 80 or less in accordance with ASTM D 676-58T, and elastic modulus from 1.times.10.sup.5 Pa to 1.times.10.sup.8 Pa at 25.degree. C., and decomposes with ease in the natural environment, under composting conditions or under hydrolysis conditions. The biodegradable aliphatic elastomer can be obtained by crosslinking aliphatic polyester containing aliphatic unsaturated polybasic acid as a polymer constituting ingredient and having a weight average molecular weight of 15,000 or more.

Biodegradable aliphatic polyester elastomer and preparation process of

A biodegradable lubricative resin composition which withstands use as a material for sliding parts, and slide bearings and gears made from such a resin composition. The resin composition contains an aliphatic polyester which is a monopolymer or copolymer of a hydroxy-carboxylic acid or an aliphatic polyhydroxy alcohol and an aliphatic polybase, the aliphatic polyester preferably containing 50-100 wt % lactic acid, and a lubricant which is a lubricating oil or a solid lubricant. Slide bearings and gears molded from such a resin composition are also proposed.

Biodegradable lubricative resin composition

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Kanagawa, Japan

Masanobu Ajioka