Patent GB-888316-A (GB)
Title: Method of preparing a urethane polymer
IPC: C08G18/24
Filed: 1959-08-19
Abstract: A method of preparing a urethane polymer comprises reacting a polyether with an organic polyisocyanate in the presence of an organotin compound, said organotin compound being present in an amount of about 0,000001 to 0,1 part by weight per part by weight of the polyether, the polyether being terminated by reactive hydrogen-containing groups which react with isocyanate, said polyisocyanate being present in an amount sufficient to react with the terminal groups of the polyether.  The process may be used to prepare an elastomer, or, by using sufficient polyisocyanate, to form a prepolymer having terminal isocyanate groups.  The prepolymer can then be added to a mixture of water and a catalyst such as N-alkylmorpholines, N,N-dialkylcyclohexylamine, trialkylamines, pyridine, quinoline, dimethylpiperazine, reaction products of N,N-diethylaminoethanol and phenylisocyanate, ester amines, dimethylbenzylamine, dimethyllaurylamine and dimethylstearylamine to give a foamed product.  Preferably, there is added to the prepolymer 0,0001 to 0,01 part of organotin compound, before the addition to the water-catalyst mixture.  Organotin compounds include alkyl, aryl, aralkyl and mixed derivatives; organotin oxide and hydroxide derivatives; dialkenyl tin oxides; compounds in which the organic groups are heterocyclic, e.g. furyl, thienyl, thenyl, pyridyl, piperidyl and pyryl; organotin salts of aliphatic, aromatic, alpha, beta-olefinic and hydroxy carboxylic acids; reaction products of a dialkyltin oxide with a fatty acid and maleic anhydride; monomeric or polymeric compounds obtained by reacting an organotin compound with a carbonyl-containing compound; compounds in which the oxygen atom of the organotin compound R2SnO has been replaced by an inorganic negative oxygen-containing radical; organotin derivatives of organic and inorganic esters; organotin phosphate esters; organotin phosphates, e.g. di-hexyl tin di-metaphosphate; organotin sulphides, mercaptoacids and ester derivatives thereof; organotin derivatives of mercaptoalcohol esters; and reaction products of organotin oxides with mercaptobenzothiazole.  The organic radicals can be substituted by ester, carboxyl, halogen and alkoxy substituents.  Specific compounds are listed.  In typical Examples (1) an addition product of propylene and ethylene oxides with ethylene diamine is reacted with toluene 2,4 and 2,6-diisocyanates in the presence dibutyl tin laurate.  The mixture is poured into a mould and formed an elastomer; (7) a prepolymer is obtained from polypropylene glycol and toluene diisocyanates in the presence of dibutyl tin laurate and is converted to a foam by treatment with water, dihydroxy propyl methyl piperazine, silicone fluids, emulsifier, triethylamine, N-methyl morpholine, didecyl phthalate, toluene diisocyanates.ALSO:A method of preparing a urethane polymer comprises reacting a polyether with an organic polyisocyanate in the presence of an organotin compound, said organotin compound being present in an amount of about 0,000001 to 0,1 part by weight per part by weight of the polyether, the polyether being terminated by reactive hydrogen-containing groups which react with isocyanate, said polyisocyanate being present in an amount sufficient to react with the terminal groups of the polyether.  The process may be used to prepare an elastomer, or, by using sufficient polyisocyanate, to form a prepolymer having terminal isocyanate groups.  The prepolymer can then be added to a mixture of water and a catalyst such as N-alkylmorpholines, N,N-dialkylcyclohexylamine, trialkylamines, pyridine, quinoline dimethylpiperazine, reaction products of N.N-diethylaminoethanol and phenylisocyanate, ester amines, dimethylbenzylamine, dimethyllaurylamine and dimethylstearylamine to give a foamed product.  Preferably, there is added to the prepolymer 0,0001 to 0,01 part of organotin compound before the addition to the water-catalyst mixture.  Organotin compounds include alkyl, aryl, aralkyl and mixed derivatives; organotin oxide and hydroxide derivatives; dialkenyl tin oxides; compounds in which the organic groups are heterocyclic e.g. furyl, thienyl, thenyl, pyridyl, piperidyl and pyryl; organotin salts of aliphatic, aromatic, alpha, beta-olefinic and hydroxy carboxylic acids; reaction products of a dialkyltin oxide with a fatty acid and maleic anhydride; monomeric or polymeric compounds obtained by reacting an organotin compound with a carbonyl-containing compound; compounds in which the oxygen atom of the organotin compound R2SnO has been replaced by an inorganic negative oxygen-containing radical; organotin derivatives of organic and inorganic esters; organotin phosphate esters; organotin phosphates e.g. dihexyl tin di-metaphosphate; organotin sulphides, mercaptoacids and ester derivatives thereof; organotin derivatives of mercaptoalcohol esters; and reaction products of organotin oxides with mercaptobenzothiazole. The organic radicals can be substituted by ester, carboxyl, halogen and alkoxy substituents specific compounds are listed.  In a typical Example (7) a prepolymer is obtained from polypropylene glycol and toluene diisocyanates in the presence of dibutyl tin laurate and is converted to a foam by addition of water, dihydroxypropyl methyl piperazine, silicone fluids, emulsifier, triethylamine, N-methyl morpholine, didecyl phthalate, toluene diisocyanates.