Toray Industries, Inc.

Natureworks LLC

Takuma Naotsuka

Hiroyuki Ome

Yoshitake Takahashi

Mitsushige Hamaguchi

Toru Takahashi

Ken Sudo

Yasuto Tachibana

A polylactic acid resin composition includes: 0.005 parts by weight to 1.2 parts by weight of a metal phosphate represented by Formula (1):MHPO&#x2003;&#x2003;(1)(in Formula (1), M is an alkali metal atom or an alkaline earth metal atom, and x, y, and z are integers satisfying 1&#x2266;x&#x2266;2, 1&#x2266;y&#x2266;4, and 2&#x2266;z&#x2266;8, respectively) with respect to 100 parts by weight of a polylactic acid resin including a poly-L-lactic acid component and a poly-D-lactic acid component, wherein a crystallization enthalpy of crystals in the polylactic acid resin is not less than 5 J/g when a temperature of the polylactic acid resin composition is increased to 250&#xb0; C., and the temperature is kept constant for 3 minutes, followed by decreasing the temperature at a cooling rate of 20&#xb0; C./min in differential scanning calorimetry.

Polylactic acid resin composition, molded product, and method of manufacturing polylactic acid resin composition

A method of producing a polylactic acid block copolymer constituted of a segment(s) composed of L-lactic acid units and a segment(s) composed of D-lactic acid units, includes obtaining a mixture by mixing poly-L-lactic acid and poly-D-lactic acid one of which has a weight average molecular weight of 60,000 to 300,000 and the other of which has a weight average molecular weight of 10,000 to 50,000, the mixture having a weight average molecular weight of not less than 90,000 and a degree of stereocomplexation (Sc) satisfying: Sc=&#x394;Hh/(&#x394;Hl+&#x394;Hh)&#xd7;100&#x3e;60 (wherein &#x394;Hh represents the heat of fusion of stereocomplex crystals (J/g), and &#x394;Hl represents the heat of fusion of crystals of poly-L-lactic acid alone and crystals of poly-D-lactic acid alone (J/g)); and subsequently subjecting the mixture to solid-phase polymerization at a temperature lower than the melting point of the mixture.

Method for producing polylactic acid block copolymer

A method for producing a crystallized polyester comprises the crystallization step of applying a shear and/or a pressure to a polyester selected from an aliphatic polyester and a polyalkylene terephthalate at a temperature of (Tm&#x2212;70&#xb0; C.) to (Tm+20&#xb0; C.), where Tm is a melting point of the polyester, thereby converting the polyester into a state having a crystallinity of 10% or more and fluidity.

Method for producing crystallized polyester

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Aichi, Japan

Takuma Naotsuka