monitoring the curing process of bismaleimide / epoxy blend by ft-ir spectroscopy

Due to its high thermal and mechanical properties, blending with bismaleimide is one of the main methods to improve the epoxy resin properties at elevated temperatures. in order to investigate the curing behaviour of epoxy / bismaleimide blend, first 4,4 - bis(maleimido) diphenylmethane was synthesized and characterized with ftir and 1hnmr spectrometry. then the synthesized bismaleimide was blended in 30 phr with epoxy resin and the obtained blend was cured with 4,4 - diamino diphenylmethane. the curing degree of each bismaleimide and epoxy resins was monitored quantitatively during the time according to their characteristics absorption bands in ft-ir spectra. the results showed that epoxy and bismaleimide resins are curing simultaneously at 160°c, while the curing rate of bismaleimide is higher than epoxy in the early of curing reaction.