Preparation and characterization of a novel thermally stable unsaturated poly(ester-imide) based on 1,4-bis[2′-trifluoromethyl-4′-(4″-carboxylic acid)trimellitimido phenoxy]benzene

A novel thermally stable unsaturated poly(ester-imide) (UPEI-50) was prepared by thermal polycondensation of a diimidodicarboxylic acid monomer, 1,4-bis[2′-trifluoromethyl-4′-(4″-carboxylic acid)trimellitimido phenoxy]benzene (BTTB), maleic anhydride and 1,2-propylene glycol. The poly(ester-imide) resin obtained was found to be easily dissolved in glycidyl methacrylate (GMA) to give a homogeneous resin composition with low viscosity, which was then thermally cured into thermosetting poly(ester-imide)/glycidyl polymethacrylate polymer composite (UPEI-50/GMA). Effects of curing processing parameters such as the curing temperature and curing time, the reactive monomer concentration and the initiator amount etc. on curing reaction were systematically investigated. Experimental results indicated that the thermally cured UPEI-50/GMA polymer composite exhibited outstanding thermal stability, mechanical and electrical insulating properties.