Process for preparing colorless hydroxyl epihalohydrin polymers
AssigneeThe B. F. Goodrich Company
InventorYoshihisa Okamoto
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Abstract
In a process for the polymerization of an epihalohydrin wherein the catalyst (initiator) employed is a trialkyl oxonium salt of an HMF.sub.6 acid wherein M is a Group V element selected from the group consisting of phosphorus, arsenic and antimony, and the polymerization is conducted in the presence of controlled amounts of water or a polyol to obtain hydroxyl containing low molecular weight polymers, a colorless polymer is obtained when the reaction product is washed with an aqueous solution of an alkal metal carbonate.
Claims7
In a process for the manufacture of hydroxyl-terminated polymers which comprises polymerizing an epihalohydrin in the presence of from about 0.03 part to 15.0 parts by weight of water or polyol, based on 100 parts by weight of the epihalohydrin, and catalytic amounts of a trialkyl oxonium salt of an HMF.sub.6 acid wherein M is an element selected from the group consisting of phosphorus, arsenic and antimony, the improvement comprising washing the polymer with an aqueous solution of an alkali metal carbonate, the amount of said metal carbonate being a molar excess over the amount of said catalyst, at a temperature of greater than 40.degree. C., whereby there is obtained a clear, colorless, heat stable polymer having a pH of about 5 to 8.
Dependencies are inferred from the claim text.