GB960009A - The use of polymeric materials in the preparation of polyurethanes and the resulting polyurethanes - Google Patents

Abstract

A polyurethane plastic is obtained by reacting with an organic polyisocyanate or polyisothiocyanate a polymeric material comprising an addition product of a halo-epoxy-substituted alkane and a nucleating agent consisting of a compound having in its molecular structure at least three active hydrogen atoms present or thiol or hydroxyl groups. The epoxy alkane may be epichlorhydrin, epibromhydrin, 1,4,dichloro 2,3 epoxy butane or 1 chloro 2,3-epoxy pentane; and an alkylene oxide such as styrene oxide, ethylene oxide, 1, 2 propylene oxide or 1, 2 butylene oxide may also be added. The preferred nucleating agents are glycerol, pentaerythritol, and sorbitol; though alpha alkyl glycerols, 1,2,5, pentanetriol, 1,2,6 hexanetriol, pentaglycerol, erythritol, pentitols or henitols may also be used. Specified catalysts are the etherate of boron trifluoride, sulphuric acid, phosphoric acid, stannic chloride, aluminium trichloride, titanium tetrachloride and the Lewis acids. The polyurethane prepolymers which contain free isocyanate or isothiocyanate radicals can be connected into the plastics by reaction with a difunctional group which may be water, glycols, diamines, dicarboxylic acids, hydroxyamines, hydroxy acids and amino acids. The resulting plastic material may be foamed using tertiary organic bases such as trimethyl-amine, N-alkylmorpholine, triethylene diamine, triethylamine, tripropylamine, tributylamine, triamylamine, tribenzylamine or dimethylaniline as catalyst. In a typical example a polymer was prepared by reacting epibromhydrin, propylene oxide, and glycerol in the presence of boron trifluoride, and this was foamed using water, triethylene diamine, silicone oil, and diphenyl methane diisocyanate. Foaming may also be effected by using difluoro-dichloro-methane or by blowing with carbon dioxide. When non-foamed polyurethane plastics are manufactured the prepolymer can be prepared in the presence of an organic solvent which may be benzene, toluene, xylene, solvent naphtha, gasoline, carbon tetrachloride, ethyl acetate or amyl acetate. Specification 868,996 is referred to.