| 摘要 |
A process for the production of foamed polyurethanes comprises reacting a polyhydroxy compound (which may also contain carboxyl groups) with a polyisocyanate in the presence of a metal catalyst and simultaneously or subsequently foaming the reaction mixture, if necessary or if desired (the latter case being when carboxyl groups are also present) with water, wherein the metal catalyst is a tetravalent tin salt of an oxime in which each tin atom is attached to an organic radical by means of at least one carbontin bond. Specified polyhydroxy compounds are alkylene oxide polymers, dihydroxy naphthalene and addition products of alkylene oxides with di- or polyhydric alcohols and phenols, aliphatic or aromatic mono- and polyamines containing at least two active hydrogen atoms, aminoalcohols containing at least two active hydrogen atoms and polyesters. Specified polyisocyanates are phenylene, toluylene and 4:4-diphenylmethane, diisocyanates, reaction products thereof with glycerine, trimethylol propane, hexanediol and hexanetriol and isocyanate polymers. Many tin compounds are specified, examples being the transesterification product of dibutyl-tin-dimethoxide with isobutyraldoxime, the transesterification product of dibutyl-tin-dimethoxide with N:N-diethylaminopentanone-2-oxime and the reaction product of diacetyl dioxime and dibutyl-tin-dimethoxide. The process of the invention may be effected in the presence of emulsifiers, e.g. sulphonated castor oil, foam stabilizers, e.g. silicone-alkylene oxide copolymers, silicones containing basic nitrogen atoms, cell regulators, e.g. paraffin and silicone oils and accelerators, e.g. dimethyl benzylamine, 1-alkoxy-3-dialkylaminopropane, endoethylene piperazine, permethylated N-ethylaminopiperazine and alkali metal hydroxides, carbonates, phenolates and alcoholates. Many examples are given. Specifications 769,680, 769,681, 769,682, 843,841, 884,781 and German Specifications 964,988 and 1,040,251 are referred to.ALSO:Tetravalent tin salts of oximes in which each tin atom is attached to an organic radical by means of at least one carbon-tin bond are made by:-(1) transesterifying dibutyl-tin-dimethoxide with isobutyraldoxime; (2) transesterifying CH3-O-(Sn(C4H3)2O)nCH3 (where n = 1.5) with isobutyraldoxime; (3) transesterifying dibutyl-tin-dimethoxide with heptylaldoxime; (5) transesterifying dibutyl-tin-dimethoxide and N : N-diethylaminopentanone-2-oxime; (6) transesterifying dibutyl-tin-dimethoxide with N : N11 : N111-trimethyl-N1-(b -aminoethyl)-piperazine; (9) reacting dibutyl-tin-dimethoxide with diacetyl dioxime; (10) transesterifying dioctyl tin dimethoxide with 1-diethylamino pentanone-4-oxime and (11) transesterifying triethyl-tin-methoxide with 1-diethylamino pentanone-4-oxime. U.S.A. Specification 2,727,917 is referred to.ALSO:A process for the production of foamed poly-urethanes comprises reacting a polyhydroxy compound (which may also contain carboxyl groups) with a polyisocyanate in the presence of a metal catalyst and simultaneously or subsequently foaming the reaction mixture, if necessary or if desired (the latter case being when carboxyl groups are also present) with water, wherein the metal catalyst is a tetravalent tin salt of an oxime in which each tin atom is attached to an organic radical by means of at least one carbon-tin bond. Specified polyhydroxy compounds are alkylene oxide polymers, dihydroxy napthalenes and addition products of alkylene oxides with di- or polyhydric alcohols and phenols, aliphatic or aromatic mono- and polyamines containing at least two active hydrogen atoms, aminoalcohols containing at least two active hydrogen atoms and polyesters. Specified polyisocyanates are phenylene, toluylene and 4 : 41-diphenylmethane diisocyanate, reaction products thereof with glycerine, trimethylol propane, hexane diol and hexanetriol and isocyanate polymers. Many tin compounds are specified, examples being the transesterification product of dibutyl-tin-dimethoxide with isobutyraldoxime, the transesterification product of dibutyl-tin dimethoxide with N :N-diethylaminophentanone-2-oxime and the reaction product of diacetyl dioxime and dibutyl-tin-dimethoxide. The process of the invention may be effected in the presence of emulsifiers e.g. sulphonated castor oil, foam stabilisers e.g. silicone-alkylene oxide copolymers, silicones containing basic nitrogen atoms, cell regulators e.g. paraffin and silicone oils and accelerators e.g. dimethyl benzylamine, 1-alkoxy-3-dialkylamino propane, endoethylene piperazine, permethylated N-ethylamino-piperazine and alkali metal hydroxides, carbonates, phenolates and alcoholates. Many examples are given. Specifications 769,680, 769,681, 769,682, 843,841, 884,781 and German Specifications 964,988 and 1,040,251 are referred to. |
