Co:polyether preparation from tetra:hydro-furan and cyclic ether, useful on industrial scale

摘要

Polyether preparation comprises: (a) copolymerising tetrahydrofuran (THF) and copolymerisable cyclic ether(s) using an untreated hetero-poly-acid (I) as catalyst in the presence of a hydroxyl (OH) compound, giving a reaction liquid (II); (b) contacting (II) with an anion exchange resin to remove (I) by adsorption; (c) desorbing (I) from the resin for re-use as catalyst; and (d) re-using the resin. Also claimed are the method of recovering (I) and for re-using (I) in this process. Pref. the other cyclic ether is an ethylene oxide or oxetan derivative and is used in an amount of 5-100 wt.% with respect to the amount of THF. This has >= 1 OH group in the molecular and is used in an amount of 1-50 wt.% with respect to THF and cyclic ether. (I) contains 20-40 molecules of water of hydration per molecule of hetero-poly-acid. It contains molybdenum (Mo) or tungsten (W) and especially is molybdato- or tungstato-phosphoric or -silicic acid. The resin is a styrene-divinylbenzene copolymer or acrylic resin with amino, substituted amino or quaternary amino groups. (I) desorbed from the resin is treated with an acid, preferably by contact with a strongly acidic cation exchange resin, especially a styrene, (meth)acrylic, phenol or amino condensation-type resin containing sulphonyl groups, and all the acid-treated (I) is used as catalyst.