Patent ID: 7544763

Claim:
A method for making an fatty acid ester oil-based polyol consisting of the following steps: a) epoxidizing a fatty acid ester oil, in a presence of acid catalyst, consisting of hydrogen peroxide and an acid to form an epoxidized oil b) separating said epoxidized oil from the aqueous phase, c) washing said separated epoxidized oil with water to remove residual hydrogen peroxide and acid, d) optionally drying or partially drying the epoxidized oil under vacuum, e) admixing said epoxidized oil with one or more alcohols, water, or a mixture thereof, wherein no acid catalyst is added to the reaction mixture, f) heating the alcohol/epoxidized oil to reflux to form by hydroxylation an oil-based polyol, wherein the oxirane content of the polyol is less than 0.2% by weight, and wherein said alcohols are mono-alcohols.