Research On Heat Resistant Epoxy Resin System And Its Composite Properties For Liquid Composite Molding

Nowadays, epoxy resin composite has the wide prospective applications in aerospace field. In order to meet the requirement of heat resistance and liquid composite molding, the method of orthogonal design was adopted and two kinds of resin systems were chosen. Heat resistance, viscosity properties, curing process of these two kinds of epoxy resin systems as well as the mechanical property of the composite, were systematically studied in this paper. The main research work and results are as follows:The method of orthogonal design was adopted to design the formulae of different kinds of resin systems and DSC method was used to characterize the glass transition temperatures(T_g) of the resin systems. Two kinds of epoxy resin systems with good heat resistance were chosen out, which were:(1) formula 1: MF4101/ZH-110/DMP-30(mass ratio 100:130:1), T_g reached 215.4? and Heat Distortion Temperature(HDT) reached 187.1?;(2) formula 2: MF-4101/MHR-070/ZH-110/DMP-30(mass ratio 100:20:150: 1.5), T_g reached 184.4? and HDT reached 177.0?.Rheometer was adopted to measure the viscosity properties and DSC method was used to investigate the curing properties of the preferred resin systems. Results show that resin system in formula 2 has better performance in viscosity properties than formula 1. The pre-curing temperatures of formula 1 and formula 2 are 114? and 115 ? respectively, curing temperatures are 134 ? and 138 ? respectively, and post-curing temperatures are 144? and 154? respectively.Resin casting body and fiber reinforced composite were made by the resin systems in the two preferred formulae and their tensile and flexural properties were tested. The results show that the mechanical properties of formula 2 are better than those of formula 1. The tensile and flexural strength of formula 2 at room temperature are 902 MPa and 1490 MPa, and the tensile and flexural modulus of formula 2 at room temperature are 40.49 GPa and 43.46GPa; The tensile and flexural strength of formula 2 under high temperature(150?) are 759 MPa and 850 MPa, and the tensile and flexural modulus of formula 2 at 150? are 38.98 GPa and 37.43 GPa.In conclusion, formula 2 is a kind of heat resistant resin system which is suitable for liquid composite molding.