Patent ID: 8409677

Claim:
A composition comprising, based on the weight of the composition, 40 to 70 weight % of an aliphatic-aromatic copolyester, 20 to 50 weight % of starch, 5 to 10 weight % of polyol plasticizer, and 0 to 10 weight % of water wherein the copolyester comprises a dicarboxylic acid component and a glycol component; the dicarboxylic acid component comprises, based on 100 mole % total acid component, about 80 to 40 mole % of a first aromatic dicarboxylic acid consisting essentially of a terephthalic acid component, about 10 to 60 mole percent of a linear aliphatic dicarboxylic acid component; and 0 to 30 mole percent of an additional dicarboxylic acid component; the additional dicarboxylic acid is selected from the group consisting of a second aromatic dicarboxylic acid, an alicyclic dicarboxylic acid, a branched dicarboxylic acid component, and combinations of two or more thereof; the glycol component consists essentially of, based on 100 mole percent total glycol component, about 100 to 60 mole percent of a linear aliphatic glycol component, 0 to about 4 mole percent of a dialkylene glycol component; and 0 to 40 mole percent of an additional glycol; the additional glycol component is selected from the group consisting of an alicyclic glycol component and a branched glycol component; the additional dicarboxylic acid component, the additional glycol component, and the branched hydroxy-carboxylic acid component is at least 2 mole % of the copolyester; and a film prepared from the composition has a tear strength measured in the machine direction at least 3 times greater than the tear strength measured in the machine direction of a film made from the copolyester.