METHOD OF REGULATING MOLECULAR WEIGHT DISTRIBUTION OF POLYETHER GLYCOL

摘要

A method of regulating the molecular weight distribution of a polyether glycol in producing a polyether glycol having a given number-average molecular weight by polymerizing tetrahydrofuran as a feed monomer using a heteropolyacid as a catalyst, which comprises: conducting the polymerization while causing water to be present in such an amount as to form two phases consisting of an organic phase comprising the feed material and a catalyst phase; sampling the polymerization product during the polymerization to determine the molecular weight distribution thereof; and then regulating the distribution of monomer residence time in the catalyst phase in such a manner that the residence time distribution is widened when the found molecular weight distribution is narrower than the target molecular weight distribution, and is narrowed when that found distribution is wider than the target molecular weight distribution.