| 摘要 |
1381123 Curing agents for epoxy resins SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ NV 9 March 1972 [11 March 1971 8 Sept 1971] 6569/71 and 41916/71 Headings C3B and C3P Epoxy resins are cured by curing agent compositions which comprise the reaction product of (a) one or more diprimary amines, (b) a polymer containing more than one reactive group per molecule and having a M.W. above 1000 and a reactive equivalent weight above 500, the reactive groups thereof being capable of reacting with amine and/or epoxide groups (e.g. carboxyl, hydroxyl, halogen or mercaptan groups), and optionally (c) a polyepoxide, the amount of (a) being such as to ensure that the product -contains free diprimary amine in an amount of less than 80 wt. per cent of the total. When (a), (b) and (c) are all reacted, (b) may be first reacted with (a) or (c) and the other reactant added subsequently. Suitable reactants are listed. The compositions may contain diluents, particularly benzyl alcohol, and also accelerators, e.g. salicylic acid or p-toluene sulphonamide. The following examples are given of preparing the curing agent compositions: butadiene-acrylonitrile copolymer containing either terminal carboxyl groups or both terminal and pendant carboxyl groups or terminal mercaptan groups is reacted first with 4,4<SP>1</SP>-diaminodiphenyl methane and then with the diglycidyl ester of dimerized linoleic acid, benzyl alcohol and salicylic acid being added to the product; butadiene-acrylonitrile copolymer containing either terminal carboxyl groups or terminal mercaptan groups is reacted first with the diglycidyl ester of dimerized linoleic acid (in the former case in the presence of benzyl dimethylamine as accelerator) and then with 4,4<SP>1</SP>-diaminodiphenyl methane, benzyl alcohol and salicylic acid being added to the product; butadiene-acrylonitrile copolymer containing terminal carboxyl groups is reacted with either cyclohexyl propylene diamine or 3,3<SP>1</SP>-dimethyl-4,4<SP>1</SP>-diaminodicyclohexyl methane, benzyl alcohol being added to the product; and butadiene-acrylonitrile copolymer containing both terminal and pendant carboxyl groups is reacted with a mixture of isophorone diamine and trimethylhexamethylene diamine, benzyl alcohol and p-toluene sulphonamide being added to the product. Examples are also given in which curing agent compositions prepared as described above, and in one case a mixture of two such products, are used to cure a commercial epoxy resin (" Epikote 828 "-Trade Mark) in the presence of additional materials, viz. either a mixture of red iron oxide, asbestine, talc, a silicone resin and a thixotropic agent; or a mixture of benzyl alcohol, triphenyl phosphite and magnesium oxide. |
