POLYOXALATE COPOLYMER Russian patent published in 2018 - IPC C08G63/12 C09K8/12 

FIELD: chemistry.

SUBSTANCE: present invention relates to a polyoxalate copolymer, which contains the major ester oxalate units, joined together like a straight chain, and branched ester copolymer units derived from a trifunctional or more highly functional alcohol or acid, with branched ester copolymer units contained in an amount of 0.01–1.0 mol. % on the main ester units of oxalate, the main ester units of oxalate are derived from oxalic acid or alkyloxalate and ethylene glycol or butylene glycol, the crystallization temperature of said polyoxalate copolymer, when the temperature decreases, is in the range of 30–70 °C, as measured by DSC, and indicator τ slowing down the initial hydrolysis of the specified polyoxalate copolymer is not less than 0.7, adding this polyoxalate copolymer to water at 70 °C and keeping in it, where the indicator τ slowing down the initial hydrolysis is determined by the formula: τ=Vt/Vf, in which Vt is the degree of hydrolysis from the time when 12 hours have passed, until the time when 24 hours have passed after being added to water, and Vf is the degree of hydrolysis from the moment of adding to water until the time when 12 hours have passed.

EFFECT: obtaining polyoxalate copolymer with suppressed initial hydrolysis property.

4 cl, 1 dwg, 1 tbl, 4 ex