Musashino Chemical Laboratory, Ltd.

Teijin Limited

Mutual Corporation

Other

Yuka Komazawa

Kiyotsuna Toyohara

Zhen Tang

Yoshiharu Kimura

Hirotaka Suzuki

Ryuji Nonokawa

Yasuhito Maeda

Tsuyoshi Aoki

Kazuki Fukushima

Masayuki Takada

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 provide a composition which contains polylactic acid and has excellent heat stability, mechanical strength and color. The composition contains 0.001 to 0.1 part by weight of a metal catalyst and 0.001 to 0.5 part by weight of a phosphono-fatty acid ester based on 100 parts by weight of polylactic acid.

Polylactic acid composition

It is an object of the present invention to provide a method for producing a polylactic acid block copolymer having high molecular weight, and in lower cost, wherein only a stereo-complex crystal is capable of growing, even when heat melting process is repeated. The present invention relates to a method for producing a polylactic acid block copolymer characterized in that (i) ring-opening polymerization of D-lactide (D component) is carried out in the presence of poly-L-lactic acid (L component), or (ii) ring-opening polymerization of L-lactide (L component) is carried out in the presence of poly-D-lactic acid (D component), and mass ratio of the D component and the L component is the D component/the L component=60/40 to 91/9, or the L component/the D component=60/40 to 91/9.

Method for producing polylactic acid block copolymer

Growing community of inventors

Chuo-ku, Japan

Yuka Komazawa