| Epoxy resin with its many excellent performances in the transportation, civil engineering, industrial production, military defense and other fields have been widely used, currently is one of the most widely used thermosetting resin. With the progress of industrial technology, the traditional epoxy resin in response to new performance requirements when it is some powerless, synthesizing a variety of new structure and function of epoxy resin curing agent to improve the performance of resin cured material is a commonly useful method. In this paper, a silicone-based epoxy resin curing agent was obtained by hydrolysis condensation reaction with KH550 as monomer. Its structure and cured product properties were characterized and the curing behavior of the curing system was studied. The main research contents are as follows:The epoxy resin curing agent with Si-O-Si bond as the main segment and -NH2 as the active group was synthesized by hydrolysis condensation reaction with KH550 as the reaction monomer. The effects of various reaction conditions on the product were studied. The co-solvent was the best synthesis condition of toluene and ethanol, the reaction time was 4h and temperature was 60 ?, the molar ratio of deionized water to monomer was 1.7: 1.The structure and degree of the product was characterized by FT-IR,~1HNMR, GPC and so on. Based on the analysis results, it was confirmed that the product was silicone oligomer resin, and the curing was studied by various methods agent storage, viscosity, compatibility with EP, solid content, heat resistance and other basic-properties.The characteristic temperature of the curing agent of the silicone-based curing agent and the DGEBA and the alicyclic epoxy resin was studied by non-isothermal DSC method. The optimum curing temperature was determined, and the reaction activation energy of the two systems. It was found that the activation energy of the reaction between the curing agent and the alicyclic resin was lower due to the molecular structure, and the crosslinking reaction was more likely to occur.The bonding strength of the cured material of the silicone type curing agent / E51 system was 14.4MPa, the 5% thermal decomposition temperature of the cured product was 355.7 ?, the 10% heat loss temperature for 378.6 ?, residual weight up to 26.2%.The curing temperature of the composites was determined by non-isothermal DSC method, and the effect of the addition amount of the silicone type curing agent on the properties of the cured product was studied by using the D400 curing agent and the silicone type curing agent.The tensile strength can be increased from 50.6MPa to 70.5MPa, and the elastic modulus can be increased from 2.44GPa to 3.12GPa, which is improved by 39.3%, and the tensile strength were increased by 15% and 27.9%, severally. The 5% and 10% heat loss temperature in N2 atmosphere also improved the modification effect by nearly 5%. |
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