Abstract: Polyether polyols having reduced terminal unsaturation are prepared in a process comprising a first step of contacting a polyether having allyl terminal unsaturation with an isomerization catalyst whereby the allyl terminal unsaturation of the polyether is reduced by at least 90% conversion to propenyl terminal unsaturation in one step and, in a final step, the resulting polyether product of the first step is contacted with an acid catalyst whereby a substantial amount of the propenyl terminal unsaturation of the polyether is removed and the corresponding polyether having an additional hydroxyl group is obtained.

Abstract: Disclosed is an improved process for polymerization of tetrahydrofuran to prepare poly(tetrahydrofuran) products with a MW range of 200 to 5000 and a dispersity of <2, which comprises premixing a carboxylic anhydride, such as, for example acetic anhydride and a dealuminated Y-zeolite and subsequently adding tetrahydrofuran at a temperature below 100.degree. C., wherein the order of addition of reactants is critical and the yield is improved by premixing the acetic anhydride and zeolite and then adding tetrahydrofuran.