abstract |
(57) Abstract: The present invention relates to the provision of a microbial degradable stretched film having excellent mechanical strength, transparency, heat resistance and microbial degradability. SOLUTION: A composition comprising a copolymer of 3-hydroxybutyrate and 3-hydroxyvalerate having a specified blending ratio and a polylactic acid-based polymer as essential components is melt-kneaded by an extruder. After being extruded and cooled, the stretched film is stretched in at least one direction at a specified magnification to provide a stretched biodegradable film having excellent mechanical strength, transparency, heat resistance and biodegradability. |