Curing behavior and properties of Fe₃O₄ areogels/epoxidized hyperbranched polyesters/epoxy resin systems

Curing process and curing kinetics of Fe₃O₄ areogels/epoxidized hyperbranched polyesters (EHBP)/epoxy resin (EP) systems were investigated by the non-isothermal DSC under different heating rates. Apparent activation energy of the curing systems was calculated by Kissinger method and Ozawa method respectively, and the reaction order was calculated according to Crane formula. Based on the DSC data, the curing process of the curing systems is 100℃ 2h→120℃ 2h→140℃ 1.5h, and the mechanical properties of the composites according to the curing processes were tested by the mechanics performance test. The results indicate that the lower content of Fe₃O₄ areogels could keep excellent mechanical properties of epoxy resin. When the mass fraction of Fe₃O₄ areogels is 1%, the tensile strength and impact strength are 61.67 MPa and 16.36 kJ/m², respectively, the density is 1.204 g/cm³, and the reflectivity is below -10 dB in the range of 8~18GHz.