Biodisintegrable thermoplastic resin moldings and a process for producing same

Claim 1

A process for producing biodisintegrable thermoplastic resin moldings which comprises extruding a melt-kneaded mixture of 25-60 weight % of an aliphatic polyester resin A and 75-40 weight % of another type of thermoplastic resin B through a die positioned at the front end of the extruder under the condition satisfying the following expressions: 10>η.sub.B /η.sub.A ≧1, (I) η.sub.A ≧500 (II) wherein η A stands for the viscosity in terms of poise of the aliphatic polyester resin at the extrusion temperature, and η B stands for the viscosity in terms of poise of said another type of thermoplastic resin at the extrusion temperature, whereby said polyester resin forms a continuous phase with said another resin dispersed as a discontinuous phase therein, wherein said aliphatic polyester resin A is selected from the group consisting of polycondensates of an aliphatic polycarboxylic acid with an aliphatic polyhydric alcohol, polycondensates of an aliphatic hydroxycarboxylic acid and ring-opened polycondensates of a lactone, and wherein thermoplastic resin B is selected from the group consisting of homopolymers and copolymers of olefins, styrenes, vinyl compounds, acrylic compounds, lactams, and combinations of polycarboxylic acids and polyamines.