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In this study, the gallic acid-based epoxy resin (GA-ER) and alkali-catalysed biphenyl-4,4 0 -diol formaldehyde resin (BPFR) are synthesized. Glass fibre-reinforced GA-ER/BPFR composites are prepared. Graphene oxide (GO) is used to improve the mechanical and thermal properties of GA-ER/BPFR composites. Dynamic mechanical properties and thermal, mechanical, and electrical properties of the composites with different GO content are characterized. The results demonstrate that GO can enhance the mechanical and thermal properties of the composites. The glass transition temperature, T g , of the BPFR/GA-ER/GO composites is 20.78C higher than the pure resin system, and the 5% weight loss temperature, T d5 , is enhanced approximately 56.68C. When the BPFR: GA-ER mass ratio is at 4 : 6 and GO content is 1.0-1.2 wt %, the tensile and impact strengths of composites are 60.97 MPa and 32.08 kJ/m 2 higher than the pure resin composites, respectively. BPFR/GA-ER composites have better mechanical properties, and can replace common BPA epoxy resins in the fabrication of composites.

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The liquid crystalline epoxy resin p-phenylene di[4-2-(2,3-epoxypropyl)ethoxy] benzoate (PEPEB) was synthesized. The curing behavior of the liquid crystalline epoxy resin (LCER) with 4,4-diaminodiphenylmethane (DDM) was studied by fourier transform infrared (FTIR), differential scanning calorimetry (DSC), and torsional braid analysis (TBA). Morphology of curing product was observed by polarized optical microscopy (POM) at different temperatures. Nonisothermal curing kinetics of this system were investigated by DSC. Results show that the PEPEB has a smectic liquid crystalline structure, and the melting point, T m , is 119 C, the clearing point is 184 C. The cured-system's gel point, T I , is 83.5 C; cure temperature, T P , is 111.6 C; and the disposal temperature, T f , is 145.8 C; activation energy of curing reaction is 4.84 KJ/ mol. Observation by POM shows that with the upgrade of initial curing temperature, the filament structure of this system transferred from anisotropy to isotropy.

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