METHOD FOR REDUCING AVERAGE MOLECULAR WEIGHT OF COPOLYMERIZED POLYETHER GLYCOL CONTAINING POLYOXYTETRAMETHYLENE GLYCOL OR OXYTETRAMETHYLENE GROUP

摘要

Purpose: a kind of method is arranged to exclusion demand to pre- monomer in the serious conversion of PTMG or PTMG- type polyether polyol for reducing the average molecular weight of copolyether polyalcohol. Construction: a kind of method has 0. for reducing the average molecular weight of PTMG or PTMG- type polyether polyol according to the present invention comprising steps of a) reacting PTMG or PTMG- types polyether polyolThe high molecular weight and perhalobenzoic acid of the temperature for arriving 250C 100 of the PTMG esters of 1 to 8 hours production PTMG- types polyetherglycol esters, it has a number-average molecular weight, lower than PTMG the or PTMG- type polyether polyol of the original charge; B) hydrolysis or the additional decomposition production of above-mentioned alcohol obtain the PTMG esters of the polyetherglycol esters of the PTMG typewritings of PTMG or PTMG- types polyether polyol, have low molecular weight.