| Advanced Polymeric Composite (APC) is one of the most important materials that have good potential usages in various fields, especially in industry of aerospace due to its good thermal and mechanical stability. Epoxy resins as one type of thermoset materials were widely developed for difference usages, which including the industry of machine, electronic, and aerospace etc. Epoxy resins gradually become more and more important materials in the industrious field. Recently wide attentions have been assigned to the modification of epoxy resin. And more and more characteristics of epoxy resins need to be improved due to the development of it. So the modification of custom epoxy resins and development of novel epoxy resins with special structures were widely investigated. To the materials that composed of epoxy resin and curing agent, some of the properties such as the fluidity and toughness have limited their usages. The modification of epoxy resin was one of works that should be urgently carried out. The modification of epoxy resins including many factors: such as the control of the fluidity of liquid material, the decreasing of the inner stress which occurs during the curing and the improvement of the toughness of the product etc. All these modification will need assistant agent as modificative agent to complete it.The advanced epoxy resin usually including the following three properties: good thermal stability, high toughness and water-fast. The relationship among them was very closely. For example, the improvement of the intensity of crosslinking will improve the thermal stability of the resulting polymers but the toughness of them will greatly decrease. Many work concluded that: the relationship between thethermal property and toughness property was incompatible. The increasing one will lead to the decreasing of the other. For this reason, we have carried out this work to search the balance of them. We try to solve this problem according to the modification of the structure of the epoxy resins. In this article, we have introduced the rigid backbone (biphenyl) into epoxy resin to improve the thermal stability. The toughness of them will be improved by the method of chain extending. A novel type of epoxy resin which has long rigid chains was prepared to improve the properties of it. Its properties such as thermal stability, dissolubility were studied in details. Further more the curing process was studied in detail. The mechanism of the curing reaction was characterized. This work will play a very important role in developing excellent epoxy resins.In chapter Two, we have successfully synthesized the epoxy resin with poly ether sulfone chain and the oligomer. The results of FT-IR, NMR, DSC were agreed with supposed structure. The epoxy resins are solid under room temperature. The thermal properties of epoxy resins with poly ether sulfone chain have been progressed, which is our purpose of the thesis design.hi chapter Three, we used the amide curing agents DDM, DDS, BADK which was synthesized to study the curing performance. First, we studied the curing kinetics of the epoxy resin to sure the curing reaction condition. The results of the study shows that the sequence of the melt point of the curing agents above is DDS>BADK>DDM, on the contrary, the sequence of the reaction activation is DDM>BADK>DDS, which is relative with molecular structure. The reaction order of the three curing reaction is approximately the same, all complex reaction. Active...
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