To provide a sheet-shaped polyactic acid crosslinked foam which has compatibly a heat resistance and a plasticity, and is easy in its secondary molding such as vacuum molding, compression molding, and to provide an optimum preparation process therefor.
The crosslinked foam is obtained by using a biodegradable resin comprising 90-10 wt% of a polyactic acid whose melt viscosity at the temperature of 170°C and the sheer rate of 100 sec-1 is 1.0×103-1.0×104 Pa s and whose mol ratio of the (d) body and the (l) body is d/l=98/2-70/30 or d/l=2/98-30/70 and 10-90 wt% of a biodegradable polyester which is not a polyactic acid and whose melt viscosity at the temperature of 170°C and the sheer rate of 100 sec-1 is 1.0×103-1.0×105 Pa s, a heat decompositon foaming agent and a closslinking aid. The sheet-shaped polyactic acid crosslinked foam has a gel fraction of not less than 10%.
AKIMARU FUSAKICHI
TAINAKA JUNICHI
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