ROOM TEMPERATURE IONIC LIQUIDS (RTILS) AS NOVEL LATENT CURING AGENTS AND ADDITIVES FOR EPOXY RESINS

摘要

Recent work in our lab has led to the discovery that certain room temperature ionic liquidsrn(RTILs) can be utilized to initiate cure or act as additives to manage mechanical properties inrnconventional thermosetting epoxy resins such as EPON?828. This paper shows that smallrnamounts (up to 20 wt %) of a RTIL such as (1-ethyl-3-methyl imidazolium dicyanamide)rnexhibits good resin miscibility, long pot life and high thermal stability while being able to initiaterncure at elevated temperatures without the associated problems of dispersion and nonhomogenousrncure. Thermomechanical analyses shows that materials with glass transitionrntemperatures (Tg) of ～200℃ (tan δ max) can be obtained while the Tg and cross-linking densityrnare dependent on the concentration of the RTIL used. The results are confirmed by differentialrnscanning calorimetry over a range of RTIL concentrations as well. Gravimetric analysis alsornindicates that the hydrophilicity of the cured networks is dependent on the concentration of RTILrnused.