Bayer Aktiengesellschaft

Martin Hoppe

Pramod Gupta

Rolf Wiedermann

Herbert Gebauer

Hans-Joachim Sandhagen

Werner Betz

Ulrich Leyrer

High functionality, low viscosity, light colored sucrose-based polyethers are prepared by reacting a starter mixture containing i) approximately 100 parts by weight of sucrose, ii) from about 30 to about 1000 parts by weight of a low molecular weight, relatively high valency alcohol and/or an alkoxylation product of such an alcohol and iii) an alkali metal hydroxide which has been prepared at a temperature of from about 20.degree. to about 110.degree. C. with an alkylene oxide at a temperature of from about 90.degree. to about 130.degree. C. and at a pressure of from about 0.3 to about 4 bar excess nitrogen pressure. These polyether polyols are particularly useful for the production of polyurethanes, particularly rigid polyurethane foams.

Process for the production of low viscosity high functionality, light

An isocyanate terminated prepolymer based upon diphenylmethane isocyanates. This prepolymer is the reaction product of a diphenylmethane isocyanate mixture having from about 75 to about 95 wt % binuclear isomers and from about 5 to about 25 wt % polymeric isocyanate with a polyether polyol. The binuclear isomer content is generally from about 15 to about 40 wt % 2,4'-isomer and from about 2 to about 10 wt % 2,2'-isomer. The polyether polyol has a functionality of from about 3 to about 8, an OH number of from about 350 to about 1000 mg KOH/g and a molecular weight of from about 150 to about 1000. These prepolymers are particularly useful as starting materials for the production of light-colored, dimensionally stable rigid polyurethane foams.

Liquid, light-colored polyisocyanate mixtures and a process for their

Growing community of inventors

Leverkusen, Germany

Martin Hoppe