Process for preparing low unsaturation polyether polyols
AssigneeHuntsman Petrochemical Corporation
InventorTimothy L. Lambert
Life of this patent
Estimating the term…
Abstract
Polyether polyols having reduced terminal unsaturation are prepared in a process comprising a first step comprising reacting propylene oxide with an initiator having at least two hydroxyl groups in the presence of a basic catalyst, a second step of contacting the polyether product of the first step 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.
Claims11
A process for preparing a polyether polyol having reduced terminal unsaturation comprising (1) reacting propylene oxide with an initiator having at least two hydroxyl groups in the presence of a basic catalyst at a temperature of about 90 to about 150.degree. C., at least a portion of the resulting polyether polyol product being characterized by having allyl terminal unsaturation, (2) heating the polyether polyol of step (1) containing the basic catalyst at a temperature of about 110 to about 190.degree. C. whereby the allyl terminal unsaturation is reduced by conversion to propenyl terminal unsaturation, where the amount of conversion is at least 90% in a single step (3) removing the basic catalyst from the polyether polyol product of step (2), and (4) contacting the polyether polyol product of step (3) with an acidic zeolite whereby a substantial amount of the propenyl terminal unsaturation is removed and the corresponding polyether polyol is obtained.
Dependencies are inferred from the claim text.