Study On The Preparation And Curing Of Esis And Increase The Toughness Of Epoxy Resin

As a special kind of thermoplastic elastomer, polystyrene-isoprene-styrene(SIS)has special rheological property, which can be used as Hot-melt pressure-sensitive adhesive. But it has a poor adhesive performance with polarity materials and a limited application because of its unsaturation double bond. Its polarity can be effectively enhanced through producing epoxy groups by H2O2and HCOOH in double bond,30%-40%of concentrated solution is stable through distilling. Through the research, we must neutralize the residual formic acid, or the epoxide value of ESIS would be seriously influenced. It produced subtle influence to the epoxide value distilling in the alcaline environment. The main impurity after drying ESIS is toluol. Through high performance liquid chromatography Drying the ESIS in60℃after4hours, there may be1%of toluol in ESIS dried in60℃after4hours; but ESIS dried in100℃after4hours,you will not find any impurity.We use the active group of ESIS, epoxy group, double bond,hydroxyl to produce chemical crosslinking point, It showed that anhydride, isocyanate, BPO can each react with epoxy groups,-OH, and double bonds by FTIR, this paper studied ESIS react with MNA, the results of ESIS curing was characterized by DSC and FIIR, it was found that, MNA can reacted with few epoxy group of ESIS, the Tg of cured ESIS increased by25℃from the results of DMA, the temperature resistance of cured ESIS increased by nearly20℃.The tensile cures of ESIS and cured ESIS performed changes from rubber to plastic, the strength of cured ESIS also increased to22MPa.Epoxy resin is used in many industries, but the weakness of epoxy resin is brittleness, this paper made use of ESIS which had physical crosslinking net and chemical crosslinking net after curing to pruduce IPN and increase the toughness of epoxy resin, the different net was achieve form different curing agents. On the precondition of mechanics strength not decreasing much, increase the toughness of epoxy resin. When adding ESIS to epoxy for T403curing system, the best content of ESIS was2-3phr, for MNA curing system, ESIS will decrease gel time as the increasing of ESIS, the right content of ESIS was8phr. When the value of tensile strength doesn’t decrease much, the value of impact strength can enhance32%(T403)and41%(MNA) than pure epoxy resin.501/ESIS as toughness agent added into epoxy system,501can increase the compatibility of ESIS and epoxy resin, on the same condition, the tensile strength of ESIS/E51/501was bigger than ESIS melting in E51.