Synthesis Of Polyamide Curing Agent And Glycidyl Ether Giluent And Studies Of Their Performance As Modifier

Comparing with other thermosetting resin, epoxy resin possesses its unique excellent performance, because it consists of such polar groups and active groups as epoxy base, hydroxyl, ether. Epoxy adhesive which can meet many practical applications, offering distinctive performances, whereas other kinds of thermosetting resin have not represented yet, can be prepared by blending epoxy resin with epoxy resin curing agent, promoting agents, modifier and additives. To satisfy the requirement of application for different fields, the focus of researchers worldwide on the modification of epoxy resin curing agent is strengthened recently, resulting in numerously valuable experiences. Moreover, investigation of the influence of different modification materials and conditions on the modified products and exploitation of new modification methods or the synthesis of new epoxy curing agent are still intriguing to scientists dedicated to epoxy adhesive. This thesis mainly investigates the mechanical properties and thermodynamic properties of epoxy adhesive using polyamide as curing agent or modified with epoxy thinners, which contribute considerably to designing formula and show great potential for industrial application.In the first part, polyamide class curing agents with relatively low molecular weight was synthesized by tuning the ratio of acid with respect to amine, followed by molecular structure characterization and essential tests about their physical properties. Then the well prepared polyamide was mixed with epoxy resin according to different weight ratio, and afterwards the effect of curing process on thermal properties mechanical properties was investigated. The results indicated that the curing rate under room temperature is relatively slow, costing about 7 days, while the curing process can be completed totally within 4h at 120℃. Moreover, the tensile strength of epoxy resin cured at 120℃could reach lOMPa, which is proved much higher than that cured at room temperature. Noticeably, the value of Tg of epoxy resin which had undergone curing process is higher than that without any treatment and polyamide itself, and increased with an increase in polyamide content relative to epoxy resin,In the second part, epoxy adhesive was modified with glycidyl ether class epoxy thinner in which synthetic process condition of RDGE was improved. Influence of reaction condition on product was investigated via the orthogonal experiment and single factor analysis method. Finally, E-44 was sequentially blended with RDGE described before. The relationship, between the viscosities of the hybrid system and composition or temperature, was investigated respectively. Most importantly, mechanical properties of all the blends were tested thoroughly here.