GB896437A - Improvements in or relating to the manufacture of polymeric materials - Google Patents

Abstract

A process for the manufacture of foamed polyurethane products by the interaction of secondary hydroxyl-ended polyethers and organic polyisocyanates or the isocyanate-ended reaction products of secondary hydroxyl-ended polyethers and organic polyisocyanates with water in the presence of a catalyst, is characterized in that the catalyst comprises an N-alkyl pyrrolidine. By an N-alkylpyrrolidine is meant a compound containing at least one pyrrolidine ring which carries an alkyl substituent on the nitrogen atom; the pyrrolidine ring and/or the alkyl group may carry other substituents. Suitable compounds are N-methyl, ethyl, propyl, butyl and octylpyrrolidines, 1:6-bis(pyrrolidino)hexane, 3:7-dimethyl 3:7-diaza bicyclo(3.3.0)octane and compounds of the general formula <FORM:0896437/IV (a)/1> where n is 0 or an integer from 1 to 6. As well as polymerization products of cyclic oxides there can also be used polyethers obtained by reaction of cyclic oxides with water, glycols, di- or polyethylene glycols, glyerol, triethanolamine, trimethylolpropane, pentaerythritol, sorbitol, sucrose, ethylene diamine, diethanolamine or dihydroxy stearic acid. The amount of polyisocyanate used is preferably such that after reaction with the end groups of the polyether, there is an excess of 3% to 5% by weight over the amount equivalent to the water used. The reaction may be modified by the incorporation of other ingredients and catalysts such as dimethylcyclohexylamine, N-methylmorpholine, potassium carbonate, potassium acetate, potassium naphthenate, manganous and manganic acetyl-acetonates, dialkyl tin compounds, ricinoleic acid, surface-active agents, silicone oil, ethyl cellulose, trimethylol propane, pigments, plasticizers such as dialkyl phthalates, tri-(b -chlorethyl) phosphate and antimony compounds.ALSO:A process for the manufacture of foamed polyurethane products by the interaction of secondary hydroxyl-ended polyethers and organic polyisocyanates or the isocyanate-ended reaction products of secondary hydroxyl-ended polyethers and organic polyisocyanates with water in the presence of a catalyst is characterized in that the catalyst comprises an N-alkyl pyrrolidine. By an N-alkyl-pyrrolidine is meant a compound containing at least one pyrrolidine ring which carries an alkyl substituent on the nitrogen atom; the pyrrolidine ring and/or the alkyl group may carry other substituents. Suitable compounds are N-methyl, ethyl, propyl, butyl and octylpyrrolidines, 1:6-bis (pyrrolidino)-hexane, 3:7-dimethyl 3:7-diaza bicyclo-(3.3.0) octane and compounds of the formula <FORM:0896437/V/1> where n is O or an integer from 1 to 6. As well as polymerization products of cyclic oxides there can also be used polyethers obtained by reaction of cyclic oxides with water, glycols, di- or polyethylene glycols, glycerol, triethanolamine, trimethylolpropane, pentaerythritol, sorbitol, sucrose, ethylene diamine diethanolamine or dihydroxy-stearic acid. The amount of polyisocyanate used is preferably such that after reaction with the end groups of the polyether, there is an excess of 3% to 5% by weight over the amount equivalent to the water used. The reaction may be modified by the incorporation of other ingredients and catalysts such as dimethylcyclohexylamine, N-methyl-morpholine, potassium carbonate, potassium naphthenate, managanous and manganic acetyl-acetonates, dialkyl tin compounds, ricinoleic acid surface-active agents, silicone oil, ethyl cellulose, trimethylol propane, pigments, plasticisers such as dialkyl phthalates, tri-(b -chlorethyl) phosphate and antimony compounds.