| abstract |
PURPOSE: To prepare a polyester of high polymerization degree, having few terminal carboxyl groups, in a short time, by the reaction of a powdered saturated polyester with a bisoxazoline at a temperature below the melting point of the polyester. n CONSTITUTION: A powdered saturated polyester is reacted with 0.1W10wt%, based on the polyester, bisoxazoline of the formula (wherein R 1 WR 8 are H or monovalent organic group; D is a bivalent organic group; n is 0.1), at a temperature below the melting point of said polyester. An aromatic dicarboxylic acid, particularly therephthalic acid is preferable as an acid component which constitutes the saturated polyester, and ethylene glycol or tetramethylene glycol is particularly preferable as a glycol component. The bisoxyazoline of the formula is particularly preferably one of the formula, where n is 0. n COPYRIGHT: (C)1981,JPO&Japio |