| 简介 |
The present invention provides a continuous process for the preparation of a polyoxyalkylene polyether product of number average molecular weight N employing continuous addition of starter, involving a) establishing in a continuous reactor a first portion of a catalyst/initial starter mixture effective initiate polyoxyalkylation of the initial starter after introduction of alkylene oxide into the continuous reactor, b) continuously introducing into the continuous reactor one or more alkylene oxides, c) continuously introducing into the continuous reactor one or more continuously added starters which may be the same or different than said initial starter, d) continuously introducing into the reactor fresh catalyst and/or further catalyst/further starter mixture such that the catalytic activity is maintained, wherein the catalyst is selected from the group consisting of modified oxides and hydroxides of calcium, strontium and barium, lanthanum phosphates or lanthanide series (rare earth) phosphates and hydrotalcites and synthetic hydrotalcites, e) polyoxyalkylating combined starters by continuously practicing at least steps b) through d) herein until a polyoxyalkylene polyether product of number average molecular weight N is obtained and f) continuously removing the polyoxyalkylene polyether product from the continuous reactor. Modified-calcium hydroxide or modified calcium oxide and lanthanum phosphate catalysts exhibit catch-up kinetics and are thus useful for the production of polyalkylene oxides using the continuous and CAOS processes. |
客服热线：
手机版
二维码
