Loading patent…
AssigneeHodogaya Chemical Co., Ltd.
InventorsHiroshi Nakaoka, Hideyuki Ishii, Masami Suganami
Estimating the term…
An industrially advantageous process described below has been established wherein tetrahydrofuran and a cyclic ether copolymerizable therewith are copolymerized by the use of a very small amount of a commercially available heteropolyacid as it is untreated, the heteropolyacid of the catalyst is recovered, recycled and reused in a simple way, and a high quality polyether substantially free from catalyst contaminants is obtained. A process for producing a polyether, comprising the steps of copolymerizing tetrahydrofuran and at least one cyclic ether copolymerizable therewith by the use of an untreated heteropolyacid as a catalyst in the presence of a hydroxy compound to form a reaction liquid, contacting the resulting reaction liquid with an anion exchange resin so that the heteropolyacid contained in the reaction liquid adsorb to the anion exchange resin to remove the heteropolyacid, desorbing the removed heteropolyacid from the anion exchange resin to reuse it as the catalyst, and reusing the anion exchange resin after the desorption as it is, thus to recycle and reuse both the catalyst and the anion exchange resin.
A process for producing a polyether, comprising the steps of:
A process for recovering a heteropolyacid which comprises the combination steps of:
A process for reusing a heteropolyacid as a catalyst in a copolymerization of tetrahydrofuran and a cyclic ether copolymerizable therewith which comprises the combination steps of:
A process for reusing a hydrated heteropolyacid as a catalyst in a copolymerization of tetrahydrofuran and a cyclic ether copolymerizable, which process consists essentially of:
Dependencies are inferred from the claim text.