Abstract: A molding resin formed from a block copolymer comprising polyhydroxycarboxylic acid structural units (I), and polyester structural units (II) derived from a dicarboxylic acid and a diol; wherein the weight ratio (I)/(II) between the polyhydroxycarboxylic acid structural units (I) and the polyester structural units (II) is within a range from 95/5 to 10/90; the resin has a microphase separated structure in which either the polyhydroxycarboxylic acid structural units (I) or the polyester structural units (II) forms domains within a matrix formed by the other structural units; the average domain size of the domains is within a range from 0.08 to 5.0 ?m; and the weight average molecular weight of the molding resin is within a range from 10,000 to 400,000.

Abstract: A molding resin formed from a block copolymer comprising polyhydroxycarboxylic acid structural units (I), and polyester structural units (II) derived from a dicarboxylic acid and a diol; wherein the weight ratio (I)/(II) between the polyhydroxycarboxylic acid structural units (I) and the polyester structural units (II) is within a range from 95/5 to 10/90; the resin has a microphase separated structure in which either the polyhydroxycarboxylic acid structural units (I) or the polyester structural units (II) forms domains within a matrix formed by the other structural units; the average domain size of the domains is within a range from 0.08 to 5.0 ?m; and the weight average molecular weight of the molding resin is within a range from 10,000 to 400,000.

Abstract: A lactic acid polyester (III), having a lactic acid unit (I) and a polyester unit (II) at a weight ratio within the range of 10:90 to 90:10, a weight average molecular weight of 10,000 or more, and a glass transition temperature of 60° C. or below, imparts superior impact resistance to polyhydroxy carboxylic acids while maintaining superior flexibility and transparency and with minimal occurrence of bleedout.

Abstract: The present invention provides a biodegradable material having excellent organic compatibility, moldability, mechanical properties, biodegradability and storage stability which can be used as bone substitute material, material for osteosynthesis, bone filling material, dental material, material having controlled release of chemical, material having controlled release of physiologically active compound or the like and a process for the preparation thereof. A novel biodegradable material is provided, comprising as essential components a lactic acid-based polymer (A) consisting of structural units (a) derived from lactic acid components and polyester structural units (b) derived from dicarboxylic acid components and diol components, the weight ratio of (a)/(b) being from 98/2 to 20/80, and a calcium phosphate-based compound (B), wherein the weight ratio of (A)/(B) is from 99/1 to 30/70. A process for the preparation of such a biodegradable material is also provided.