Patent GB-799410-A (GB)
Title: Synthetic rubber-like materials
Inventor: FRANCE HAROLD
IPC: C08G18/60
Filed: 1956-01-20
Abstract: Diisocyanato-carbanilides for use in the preparation of polyurethanes (see Group IV (a)) are prepared by reacting diisocyanates with 0.5 molar proportion of water.  In this way are obtained 4 : 41-diisocyanato-carbanilide, 3 : 31-diisocyanato - 4 : 41 - dimethylcarbanilide and 3 : 31 - diisocyanato - 4 : 41 - dichlorocarbanilide. Reaction products (containing no free isocyanato groups) of phenols and polyisocyanates are prepared from the appropriate reactants, suitably in a solvent such as o-dichlorobenzene, chlorobenzene, xylene, toluene, benzene, dioxan, ethyl acetate, acetone or petroleum ether, in the presence of a catalyst such as dimethyl- or diethylcyclohexylamine.  In this general manner there are prepared reaction products of (1) to (7), (10), (11) and (13) naphthylene-1 : 5-diisocyanate and phenol, p-methoxyphenol, p-tert. butyl-phenol, methyl p-hydroxybenzoate, o-nitrophenol, 2,4-dichlorophenol and o-chlorophenol, 2-allylphenol, 2-hydroxyacetophenone and 2-hydroxydiphenyl respectively; (8) p-phenylene diisocyanate and phenol; (9) diphenylene - 2 : 4 : 41 - triisocyanate and phenol; (12) diphenylene-4 : 41-diisocyanate and phenol.  Other suitable phenols are those containing substituents such as alkyl, cycloalkyl, aralkyl, aryl, alkoxy, halogen, nitro, cyano, carbalkoxy, acyl or alkylsulphonyl groups.  Specification 767,578, [Group IV (a)], is referred to.ALSO:A process for the manufacture of synthetic rubber-like materials comprises heating together a reaction product of a polyisocyanate and a phenol, said reaction product containing no free isocyanate group, and the polymer obtained by heating together an organic diisocyanate and a substantially linear polyester or polyesteramide, prepared by condensation of one or more dicarboxylic acids and one or more bifunctional hydroxyl or amino compounds and having as terminal groups predominantly hydroxyl groups, the proportions of polyester or polyesteramide and diisocyanate used being such that the polymer formed by heating them together attains on heating a maximum Williams Plasticity Number of between 200 and 550.  The phenol reacted with the polyisocyanate may, for example, be phenol itself, p-tertiary butyl phenol, o- or p-nitrophenol or 2 : 4-dichlorophenol.  Other suitable phenols are those containing substituents such as alkyl, cycloalkyl, aralkyl, aryl, alkoxy, halogen, nitro, cyano, carbalkoxy, acyl, or alkylsulphonyl groups.  As dicarboxylic acid for the preparation of the polyester or polyesteramide/diisocyanate polymer (referred to as a "raw rubber") there may be used succinic, glutaric, adipic, alkyl adipic, azelaic, sebacic, phthalic, isophthalic or terephthalic acids.  As bifunctional compounds there can be used ethylene glycol, 1 : 2-propylene glycol, butane-1 : 3- or 1 : 4-diol, diethylene glycol, ethanolamine, hexamethylene diamine or benzidine or mixtures thereof.  Suitable diisocyanates are hexamethylene, diphenylmethane - 4 : 41 - diisocyanates, 1 : 2 - bis - (4 - isocyanatophenyl) ethane, 3,31 - dichlorodiphenylmethane - 4 : 41, diphenyl - 4 : 41, diphenyl ether - 4 : 41, naphthylene - 1 : 4 or 1 : 5, m - or p - phenylene and tolylene diisocyanates, ethylene glycol bis-(4-isocyanatophenyl) ether, 2 : 6-diisocyanatobenzofuran, and diisocyanato-carbanilides obtainable by reacting diisocyanates with a limited amount of water, such as 4 : 41-diisocyanatocarbanilide, 3 : 31 - diisocyanato - 4 : 41 - dimethyl - carbanilide and 3 : 31 - diisocyanato4 : 41 - dichlorocarbanilide.  For the preparation of the phenol/polyisocyanate reaction product there may be used, in addition to the diisocyanates already mentioned dicyclohexylmethane, xylylene, chlorophenylene - 2 : 4, 3 : 31-dimethyldiphenylene - 4 : 41, 3 : 31 - dimethoxydiphenylene - 4 : 41, and 3 : 31 - dimethyldiphenylmethane - 4 : 41 - diisocyanates, and benzene - 1 : 3 : 5, toluene - 2 : 4 : 6, diphenyl2 : 4 : 41 and triphenylmethane - 4 : 41 : 411 - triisocyanates and 2 : 4 : 41 - triisocyanatodiphenyl ether.  The polyisocyanate/phenol reaction product can be mixed with the "raw rubber" on a rubber mill together with fillers, plasticizers and catalysts such as trimethylamine, dimethylcyclohexylamine or cobalt naphthenate.  In Example (1) a "raw rubber" (prepared by heating an adipic acid/ethylene glycol polyester with sufficient naphthylene-1 : 5-diisocyanate to give on heating a maximum Williams Plasticity number of 443) is cured by moulding under heat and pressure with a reaction product (containing no free isocyanate groups) from phenol and naphthylene-1 : 5-diisocyanate.  Similar examples describe the curing of a similar "raw rubber" with the reaction product of (2) to (7) naphthylene-1 : 5-diisocyanate and p-methoxyphenol, p-tert.-butylphenol, methyl p-hydroxybenzoate, o-nitrophenol, 2 : 4-dichlorophenol and o-chlorophenol respectively; (8) p-phenylene diisocyanate and phenol; (9) diphenylene-2 : 4 : 41-triisocyanate and phenol.  In further examples there are employed (10) a similar "raw rubber" of Williams Plasticity number 470 and a naphthylene - 1 : 5 - diisocyanate/2 - allylphenol reaction product; (11) a similar "raw rubber" of Williams Plasticity number 394 and a naphthylene - 1 : 5 - diisocyanate/2 - hydroxyacetophenone reaction product; (12) a similar "raw rubber" of Williams Plasticity number 490 and a diphenylene - 4 : 41 - diisocyanate/phenol reaction product; (13) the "raw rubber" used in Example (11) and a naphthylene 1 : 5-diisocyanate/2-hydroxydiphenyl reactio product. Specification 767,578 is referred to.