Low-odor, higher molecular weight polyether polyols, a process for producing them, and their use for the production of polymers, cosmetics and pharmaceutical products synthesized from polyether polyols

Abstract

Low-odor, higher molecular weight polyether polyols are produced by purifying the polyether polyols at temperatures of 110.degree. to 150.degree. C. and pressures of 10 to 70 hPa with the addition of 5 to 30% by weight of water, wherein the water is passed in finely divided form, with a droplet diameter of about 5 to 100 .mu., through the polyether polyols to be purified for a time of metered addition of 1 to 5 hours.

Description

Claims

1. In a process for the production of a polyurethane comprising reacting a polyisocyanate with an isocyanate-reactive component via the polyisocyanate polyaddition process, the imporvement wherein said isocyanate reactive component comprises a low-odor, monofunctional or polyfunctional polyether polyol having a molecular weight of from about 750 to 18,000, and a viscosity at 25.degree. C. of about 40 to 25,000 mPa.s, made by the process comprising

1) purifying polyether polyol at temperatures of about 100.degree. to 150.degree. C. and at pressures of about 10 to 70 hPa, wherein about 5 to 30.0% by weight of water, based on the quantity of polyether polyol present, is metered into said polyether polyol over a time period of about 1 hour up to about 5 hours, said water being in finely divided form and having a droplet diameter of 5 to 100.mu.,

wherein the resultant polyether polyol contains a) less than about 1.5 ppm of 2-methyl-2-pentenal, b) less than about 1.0 ppm of allyl alcohol, c) less than about 15 ppm of allyloxypropanol, d) less than about 50 ppm of dipropylene glycol allyl ether, and e) less than about 1.0 ppm of propionaldehyde.

2. The process of claim 1, wherein said polyether polyol has a molecular weight of from about 1000 to about 15,000 and a viscosity of about 50 to 10,000 mPa.s at 25.degree. C.

3. The process of claim 2, wherein said polyether polyol has a molecular weight of from about 2000 to about 12,000.

4. The process of claim 1, wherein about 7 to 25% by weight, based on the quantity of polyether polyol present, is metered into said polyether polyol over a time period of about 2 to 4 hours, said water having a droplet diameter of about 7 to 50.mu..

5. The process of claim 1, wherein said distillation is at temperatures of about 115.degree. to 140.degree. C. and at pressures of about 20 to 50 hPa.