Stabilization of polyether polyols

Claim 1

In a polyether polyol composition which is stabilized against degradation by the inclusion therein of about 500-10,000 parts per million by weight of a mixture of (1) about 15-75 percent by weight of 2,6-di-tertiarybutyl-4-methyl phenol and (2) correspondingly about 85-25 percent by weight of p,p'-dioctyl diphenyl amine, said polyether polyol having a molecular weight of about 250-8,000 and being the product of reacting a polyhydric alcohol having 2-8 hydroxy groups with an alkylene oxide having a 1,2-epoxide ring and selected from the group consisting of ethylene oxide, propylene oxide, butylene oxide and a mixture thereof, the improvement of including in said composition, as a partial replacement for said 2,6-di-tertiarybutyl-4-methyl phenol, about 25-600 parts, per million parts by weight of said polyether polyol, of a phenothiazine compound represented by the formula: ##STR2##in which each R is independently hydrogen or alkyl of 1-12 carbon atoms.