| abstract |
A new polyester resin is produced by condensation polymerization of (a) a diol component of the formula:n wherein R' is an alkylene group of 2 to 4 carbon atoms; and x and y are positive integers, the sum of them being 2 to 16 on an average, and (b) an acid component of polybasic (at least dibasic) carboxylic acid, anhydride thereof, and lower alkyl ester thereof, said acid component (b) containing 1 to 50 mol% of a dibasic carboxylic acid or anhydride thereof of the formula:n where R 2 and R 3 are saturated or unsatured hydrocarbon groups of 4 to 20 carbon atoms and 10 to 30 mol% of trimellitic acid or anhydride thereof. The polyester has improved toughness, abrasion resistance and flexibility. |