| 摘要 |
Polyesterimide resins are prepared by first reacting trimellitic acid anhydride with a diphenol diester to form the bis-trimellitic acid anhydride ester of the phenol and then reacting the bisester with a primary diamine. Specified diphenol diesters are diesters of resorcinol, hydroquinone or p,p1-dihydroxydiphenyl-propane, -methane, -sulphone or -ketone with C1- 5 monocarboxylic acids. Specified diamines are p,p1-diaminodiphenyl-ether, -sulphone and -methane. The reaction with the diamine is preferably effected in two stages, first to the polyesteramide carboxylic acid which is still soluble and may be shaped before final conversion to the polyesterimide. The reaction may be effected in a solvent, e.g. dimethylformamide, N,N1 - dimethylacetamide or N-methylpyrrolidone. The solution of the first stage product may be used as a stoving varnish. |
