| 摘要 |
PCT No. PCT/GB90/00838 Sec. 371 Date Jan. 28, 1992 Sec. 102(e) Date Jan. 28, 1992 PCT Filed May 30, 1990 PCT Pub. No. WO90/15093 PCT Pub. Date Dec. 13, 1990.Hydroxyterminated prepolymers, used in curing reactions with isocyanates to produce elastomers, are prepared by continuously adding over periods of 12-50 hours an oxetane monomer to a reaction mixture containing a diol initiator and a catalyst capable of catalyzing the cationic quasi-living cationic polymerization of the monomer, the rate of addition to maintain stoichiometric excess over the monomer. Polymerization is terminated by adding brine. Polymers of increased molecular weight and reduced impurity levels result.
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