| Because Epoxy Sheet Molding Compounds (ESMC) using epoxy resin as the matrix resin, its significantly increased temperature resistance, strength and insulating efficiency compared with UP and low contractility solve the property defects of unsaturated polyester resin SMC. For ESMC molding process is simple, with a high degree of mechanization, producing on the basis of SMC production equipment, low investment and low-cost, high production efficiency. Therefore the research of epoxy sheet molding compounds has great significance to realize leaping development of fiber-reinforced epoxy resin molding technology, decisive role to the development of China's composites industry. And the study of epoxy sheet molding compounds curing has great importance to the study of epoxy sheet molding compounds.In this paper, two different methods, Chemical Modification and Microencapsulation were used to systhsize latent curing agent for ESMC, expecting to be well stored at room temperature and cure at low-medium temperature. And some fundamental researches were done.For Chemical Modification, through the method of molecular design, modifying dicyandiamide through DDS chemically, a new kind of latent curing agent was systhsized. And then, the purification and structure were characterized by means of comparing the products' physical properties, testing melting point and using FT-IR etc. After that, reasonable synthesizing process route is obtained. Using DSC and FT-IR to research making epoxy resin adhesive from epoxy resin, the curing properties before and after EP / modified Dicyandiamide curing system were analysed, conditions of curing reaction were optimized. The results show that the curing agent after modification has good low-medium temperature curing property and longer storage. Besides, curing mechanism and curing reaction kinetics were also studied.For microencapsulation, 2-ethyl-4-methylimidazole was microencapsulated with Melting-dispersion-condensation technique, microcapsules size was in the range of several tens to several hundreds micrometers demonstrated by optical microscope, the rate of retention is 13.7% tested by TGA. The curing process of epoxy (EP / Micro) curing system using micro-capsules curing agent is studied by DSC, finding that the curing initiated temperature (To) and peak temperature rate (Tp) were higher than 10℃compared with EP/2E4MI system; room temperature storage period increased from 1 day to 2 weeks or more, which is due to the increase of EP / Micro system with low apparent activation energy. Through comparing the curing process of EP / Micro system and EP/2E4MI system, curing mechanism was the verified, demonstrating that microencapsulation cannot cause significantly change the curing mechanism.
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