The invention provides a resin composition containing poly (lactic acid) and a cellulosic ester, which are biomass type materials; a resin composition excellent in transparency, mechanical properties, and thermostability; a biaxially drawn film containing poly(lactic acid) and at least one compound selected from cellulosic esters, poly(meth)acrylates, and polyvinyl compounds having a glass transition temperature of 60°C or higher; and a biaxially drawn film excellent in transparency, mechanical properties, and thermostability. The aims of the invention can be achieved by a resin composition obtained by melt-kneading a poly(lactic acid) polymer with a weight average molecular weight of 50,000 or higher and a cellulosic ester; a resin composition excellent in transparency and having luminous transmittance of 40% or higher for visible light with 400 nm; its production method; a molded article and a film made of the resin composition; a poly(lactic acid) biaxially drawn film containing a poly(lactic acid) polymer with a weight average molecular weight of 50, 000 or higher and at least one compound selected from cellulosic esters, poly(meth)acrylates, and polyvinyl compounds having a glass transition temperature of 60°C or higher; a poly(lactic acid) biaxially drawn film excellent in transparency and having film haze of 10% or lower; and a molded article made of the film.
本发明提供了一种含有聚(
乳酸)和
纤维素酯的
树脂组合物,它们都是
生物质类材料;一种透明度、机械性能和热稳定性优异的
树脂组合物;一种双轴拉伸薄膜,它含有聚(
乳酸)和至少一种选自
纤维素酯、聚(甲基)
丙烯酸酯和聚
乙烯醇化合物的化合物,其
玻璃化转变温度为60℃或更高;以及一种透明度、机械性能和热稳定性优异的双轴拉伸薄膜。本发明的目的可以通过以下方法实现:一种通过熔融捏合重量平均分子量为 50,000 或更高的聚
乳酸聚合物和
纤维素酯而获得的
树脂组合物;一种透明度极佳且对波长为 400 纳米的可见光的透光率为 40% 或更高的
树脂组合物;其生产方法;由该
树脂组合物制成的模塑制品和薄膜;一种聚(
乳酸)双轴拉伸薄膜,该薄膜含有重量平均分子量为 50,000 或更高的聚 (
乳酸)聚合物和至少一种选自
纤维素酯、聚(甲基)
丙烯酸酯和
玻璃化转变温度为 60°C 或更高的聚
乙烯化合物的化合物;一种透明度极佳且薄膜雾度为 10% 或更低的聚 (
乳酸)双轴拉伸薄膜;以及一种由该薄膜制成的成型品。