Catalyst-free process for the manufacture of a fatty acid ester oil polyol
The present invention relates to a manufacturing process for producing a polyol from a fatty acid ester in-situ. The process does not use any added organic or inorganic acid catalyst. The polyol produced by the process is essentially free of any cation or anion. The fatty acid ester oil epoxidation and hydroxylation reactions can occur progressively in the same reactor for essentially a one-pot reaction. The polyol produced by the process is essentially free of any cation or anion. The polyol can be used to produce polyurethanes having improved properties.
1. 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.
2. The method of claim 1 wherein said fatty acid ester oil comprises one or more vegetable oils.
3. The method of claim 1 wherein said epoxidized fatty acid ester oil is fully or partially dried prior to admixing with said one or more alcohols, water or mixture thereof.
4. The method of claim 1 wherein said method is a one-pot method in which said admixing of said epoxidized fatty acid ester oil and one or more alcohols, water, or a mixture thereof occurs in the same reactor in which the epoxidized fatty acid ester oil had been epoxidized, without removing said epoxidized fatty acid ester oil from said reactor.
5. The method of claim 1 wherein said fatty acid ester oil has an epoxide content of the epoxidized oil of from 1 to 10 percent oxirane.
6. The method of claim 1 , further comprising the step of reacting hydrogen peroxide, a fatty acid oil and a per-acid catalyst to form the epoxidized fatty acid ester oil in claim 1 .
7. The method of claim 6 , wherein said per-acid is acetic acid, propionic acid, formic acid, or a mixture thereof.
8. The method of claim 6 , wherein said epoxidized fatty acid ester oil is washed to remove residual hydrogen peroxide, per-acid and sulfuric acid, prior to the addition of the alcohols and/or water in the hydroxylation step.
9. The method of claim 1 , wherein said mono-alcohols are selected from the group consisting of methanol, ethanol, propanol, butanol, and mixtures thereof.