Flexible cellular polyurethane exhibiting excellent thermal and oxidative stability can be prepared using specified complexes of organotin halides or pseudo halides with amines, phosphines or phosphine oxides as latent polymerization catalysts. These catalysts also eliminate the shrinkage that often characterizes cellular polyurethanes prepared using organotin compounds as the polymerization catalyst.

Process for preparing oxidatively stable polyurethane foam

A complex has a structure of formula (1A): SnXn·(m)L, wherein X is at least one type of halogen atoms, L is a polar solvent molecule, n is a value from 1.5 to 2.5, and m is a value from 0.3 to 1.9. A perovskite compound has a structure of formula (2A): RSnXj, wherein Sn has an oxidation number from 1.5 to 2.5, R is at least one type of a monovalent cation, X is at least one type of halogen atoms, and j is a value from 2.5 to 3.5, and the perovskite compound is free of tin oxide; or a perovskite compound has a structure of formula (2B): R2M2BiX1, wherein R is at least one type of a monovalent cation, X is at least one type of halogen atoms; M2 is a monovalent metal, and i is a value from 5.0 to 7.0.

Complex and method for producing same

Use of stannous halide alcohol complexes, typified by the complex of stannous chloride and triethylene glycol, as catalysts permits production of urethane elastomers characterized by freedom from bubbles. The novel complexes are particularly characterized by their properties; e.g. Mossbauer spectra shows a chemical shift relative to a standard and a quadrupole splitting which are not found in mere mixtures of e.g., stannous chloride and triethylene glycol.

Stannous halide complexes and their use in preparing polyurethane foams

A process for the manufacture of polyurethanes by the reaction of organic polyisocyanates with hydroxyl group containing polymers is characterized in that the said reaction is carried out in the presence of a complex compound of a stannous salt with an organic ligand which is an ether, a substituted amide a triester of phosphoric acid or a sulphoxide, provided that such a ligand contains no grouping reactive with an isocyanate group The stannous salt may be the chloride, bromide, fluoride, sulphate, orthophosphate, hypophosphite, octaphosphate, oxalate, tartrate, acetate, butyrate, hexoate, octoate, oleate or p-toluene sulphonate Suitable ethers are: di-n-propyl ether, di-n-butyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dioxan, tetrahydrofuran, tetrahydropyran, ethylene propylene and butylene oxides Substituted amides may be: dimethyl and diethyl formamides, dimethylacetamide and N-methylacetamide Suitable triesters of phosphoric acid are tri-n-butyl phosphate, tri-(b -chloroethyl) phosphate, triethylphosphate, triphenyl phosphate, dimethylethyl phosphate, tribenzyl phosphate and tricyclohexyl phosphate Sulphoxides mentioned are: dimethyl, diethyl and dibutyl sulphoxides The polyurethane may be derived from a polyether, polyester or polyesteramide which may have a molecular weight of 200-5000 Many conventional polyisocyanates are listed Foamed polyurethanes may be prepared by use of a conventional blowing agent Polymers having mainly secondary hydroxyl groups eg those derived from propylene glycol, 13-butylene glycol or glycerol are suitable for foam preparation A large number of tertiary cyclic amines for use as catalysts are listed In a typical Example (10) a mixture of oxypropylated glycerol, siloxane foam stabilizer, 4-dimethyl amino-pyridine, water and various tin complexes were mixed with tolylene diisocyanate to form a foam The tin complexes used were those of stannous chloride with tetrahydrofuran, dioxan, diethylen glycol dimethyl ether, tributyl phosphate, tri-(b -chloro-ethyl) phosphate, dimethyl formamide, dimethyl sulphoxide and stannous sulphate with dioxanALSO:Complex compounds of a stannous salt with an organic ligand which is an ether, a substituted amide, a triester of phosphoric acid or a sulphoxide, provided that such ligand contains no grouping reactive with an isocyanate group are used to catalyse polyurethane formation The stannous salt may be the chloride, bromide, fluoride, sulphate, or the phosphate, hypophosphite, metaphosphate, oxalate, tartrate, acetate, butyrate, hexoate, octoate, oleate or p-toluene sulphonate Suitable ethers are: di-n-propyl ether, di-n-butyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dioxan, tetrahydrofuran, tetrahydropyran, and ethylene propylene and butylene oxides Substituted amides may be: diethyl and dimethyl formamides, dimethyl acetamide and N-methyl acetamide Suitable triesters of phosphoric acid are tri-n-butyl phosphate, tri - (b - chloroethyl)phosphate, triethylphosphate, triphenyl phosphate, dimethyl ethyl phosphate, tribenzyl phosphate and tricyclohexyl phosphate Sulphoxides mentioned are: dimethyl, diethyl and dibutyl sulphoxides Examples describe the preparation of complexes of stannous chloride with (1) dioxan, (2) tetrahydrofuran, (4) diethylene glycol dimethyl ether, (5) tributyl phosphate, (6) tri-(b -chloroethyl)phosphate; (7) and (8) dimethyl formamide, (9) dimethyl sulphoxide, (14) N,N-dimethylacetamide, (3) stannous sulphate and dioxan, (11) stannous acetate and dimethyl formamide, (12) stannous oxalate and dimethyl formamide, (13) stannous-p-toluene sulphonate and dimethyl formamide, (15) stannous chloride dihydrate and N,N-dimethyl acetamide

Williams Derek

Papers

Improvements in or relating to the manufacture of polyurethanes