Study On Toughening Modified Epoxy Resin By Thermotropic Liquid Crystal Polymer

Epoxy resin (EP) is a kind of thermosetting resin owing good mechanical properties, dimensional stability, resistant to chemical corrosion and electrical insulation, which is widely used in aerospace fields, engineering plastics, coatings and electronic packaging materials. However, after cured with curing agent, EP resin is highly crosslinking, bring some drawbacks, such as poor impact toughness. Therefore, toughening modified EP resin has important significance.Polyurethane liquid crystalline polymer with biphenyl structure and polyimide type liquid crystalline polymer were synthesized through molecular design in this paper. Through melt blending method, BLCPU/EP, Al2O3/EP/3 wt% BLCPU and PILCP/EP blend cured systems were prepared to improve its impact toughness without sacrificing electrical insulation and thermol properties of EP.The mechanical properaties of BLCPU/EP systems were tested. The results showed that impact toughness of EP system was improved.300 wt%A12O3/EP and 300 wt%Al2O3/EP/3 wt% BLCPU systems were characterized by TMA, DMA, dielectric distant and dielectric loss tester. Compared to 300 wt%AI2O3/EP systems, thermol properties and electrical properties of 300 wt%Al2O3/EP/3 wt% BLCPU system were basically unchanged.The mechanical properties and thermostability of PILCP/EP systems were investigated, indicating that impact toughness and thermostability of the modified systems were both improved. The thermol properties and electric properties of neat EP and 5 wt% PILCP/EP systems were tested by DMA, dielectric distant and dielectric loss tester. The thermol properties of 5 wt% PILCP/EP were improved and its electrical properties were basically unchaged.