Investigation Of Toughening Of Epoxy Resin With Nano-rubber And Heat Resistant Modification With Organosilicone

In order to improve the toughness and heat resistance of the curing product of epoxy resin, research was conducted in this thesis from three aspects:the.toughening of epoxy resin with nano-particle, the preparation of organic silicon modified epoxy resin and the synthesis of epoxy resin curing agent which endows the curing product with good heat resistant ability.Nanoscale carboxy terminal butadiene-acrylonitrile (CTBN) modified epoxy resin was selected as.matrix..resin., curing agent with high curing rate and endows good heat resistance to the curing product was selected and applied, epoxy resin adhesive was prepared. The formula of the adhesive was optimized by orthogonal experimental method to achieve the highest shear strength. Results showed that the average shear strength of adhesive with the optimal formula reached21.16MPa with good heat resistance. Nano-CTBN was proved to endow the matrix resin with good toughness and the toughening mechanism was pointed out to be "hole toughening".Organic silicone modified epoxy resins were prepared from dihydroxydiphenylsilane (DSPD) and epoxy resin(E51) and the preparation conditions were optimized. A series of organic silicone modified epoxy resins(E51-DSPD-X, X stands for the mass ratio of E51and DSPD) were prepared with different DSPD and epoxy resin mass ratio and were cured with Diethylenetriamine (DETA). Results showed that the glass transition temperature(Tg) of E51-DSPD-X was higher than that of E51and increased with the increasing of mass ratio of DSPD and E51. The maximum thermal weight loss rate of the curing products of E51-DSPD-X with DETA was much lower than that of E51with DETA, while the Tg of the curing products of E51-DSPD-X with DETA was only slightly lower than that of E51with DETA, with a decrement of maximum thermal weight loss rate of up to188μg·min-1and a decrement of Tg less than3℃,When X=100:15. The curing products of the modified epoxy resin showed a higher tensile strength and modulus than of E51, SEM micrographs revealed that organic silicone modification endowed epoxy resin with good toughness with obvious corrugation on the cross section of the curing products.Epoxy resin curing agent was synthesized from3-ammonium propyl triethoxy silane(APTES) and DSPD and the preparation conditions were optimized. A series of epoxy resin curing agents (DSPD-APTES-X, X stands for the mole ratio of APTES and DSPD) were prepared with different mole ratio of APTES and DSPD. Results showed that DSPD-APTES-x possess better curing ability comparing to that of LMPA650toward E51at the same condition. The maximum thermal weight loss rate of the curing products of E51with DSPD-APTES-x, which increased with the increasing of the mole ratio of DSPD and APTES, was lower than that of E51with DETA, with a higher corresponding temperature to the maximum thermal weight loss rate of the former than the latter. The maximum thermal weight loss rate of curing product of E51with DSPD-APTES-1:4was300μg·min-1lower than that of E51with DETA, while the corresponding temperature of the former was110℃higher than the latter. However, the curing products of E51with DSPD-APTES-x showed a lower Tg than of E51with DETA. The curing products of E51with DSPD-APTES-x showed higher ensile strength and modulus than that of E51with DETA, SEM micrographs revealed that DSPD-APTES-X as curing agents endowed the curing products with better toughness comparing with DETA, with obvious corrugation on the cross section of the curing products.