Polyester resin composition and method for producing same

A biodegradable polyester resin composition, comprising:

• an aliphatic polyester (P3HA) having a repeating unit represented by formula (1):
• [—CHR—CH2—CO—O—] (1),
• wherein R is an alkyl group represented by CnH2n+1, where n is an integer of 1 or more and 15 or less;
• polybutylene adipate terephthalate (PBAT);
• hydrophilic silica (A);
• and
• at least one plasticizer (B), which is selected from glycerin ester-based compounds,
• wherein a weight ratio of the aliphatic polyester (P3HA) to the polybutylene adipate terephthalate (PBAT) is 40/60 to 50/50,
• wherein an amount of the hydrophilic silica (A) contained is 4 to 13 parts by weight with respect to 100 parts by weight of a total amount of the aliphatic polyester (P3HA) and the polybutylene adipate terephthalate (PBAT) combined, and
• wherein an amount of the plasticizer (B) contained is 4 to 13 parts by weight with respect to 100 parts by weight of the total amount of the aliphatic polyester (P3HA) and the polybutylene adipate terephthalate (PBAT) combined.