| Episulfide resin is a kind of new resin which has similar structure with epoxy resin,compared with the epoxy resin, it has fast curing rate and higher toughness, good applicationprospect reflected not only can be blended with epoxy resin, but also can be used directly, italso contains many scientific problems to explore. This paper is based on a new type ofmulti-functional epoxy resin which contain unsaturated bonds: diallyl bisphenol A-epoxyresin (DADGEBA), KSCN is used as the ring-sulfurization reagent and synthesized diallylbisphenol A-epoxy/episulfide resin (DADGEBAES), the basic properties and theperformance of application of the each matrix resin were studied and obtain some valuableresults which have guiding significance to the application and development of episulfideresin.Firstly, DADGEBA was synthesized with allyl bisphenol A (DABPA), and then useKSCN as ring-curing agent to synthesize DADGEBAES, the FTIR, NMR, DSC were used tocharacterize the structure and inherent characteristics, and we study the basic properties. Inaddition, the performance parameters are got by means of molecular dynamics simulation,such as polymer synthesis reaction transition state search; The relationship between reactionreactivity and bonds parameters, the frontier molecular orbital and Fukui function; Surfaceeffects and surface free energy between different resins and metal oxides is studied; Diffusioncoefficients of water molecule in the different resin system are calculated to evaluate thewater resistance property, and finally the unstable performance of DADGEBAES is studied.The molecular dynamics simulation method for transition state search in reaction, obtainthe transition state energy and activation energy, explore the best s conditions(4h) tosynthesis this type of episulfide resin; IR characterization showed that the DADGEBAEScontaining allylic, epoxy and episulfide group, which indicate the product is a part of the ringvulcanized multifunctional epoxy/episulfide resin; DSC spectra indicate the DADGEBAESmolecular structure is similar to that of DADGEBA, its storage performance and stability ispoor; Viscosity test results show that compared with epoxy resin E51, the viscosity isrelatively small at a certain temperature, and with a lower activation energy of viscous flow.The shortest gel time of DADGEBAES curing system show it has the highest reaction activity,the activation energy was calculated: Ea (DADGEBA system)=42.42KJ/mol, Ea(DADGEBAES system)=36.30KJ/mol, by molecular modeling and molecular key parameters, the frontier molecular orbitals and Fukui functions, the reactivity prediction isconsistent with experimental results. In mechanical property test, the shear strength ofDADGEBAES curing system bond the substrate aluminum and steel is less than DADGEBA,but which is greater than conventional E51curing system, the overall performance ofadhesive to steel is better than aluminum, In addition, the surface infiltration performance ofDADGEBAES on aluminum is more excellent by measuring contact angle, on the other hand,using molecular simulation to obtain the surface interaction energy of different resin onalumina substrate. Finally, the water absorption properties, effects of water on the shearstrength and contact angles of water on cured resins tested, the diffusion coefficients of waterin the two kinds of resin are calculated through simulation, this research can predict and guideto study the material performance of water resistance. |
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