▎ 摘　　要

Thermal characteristics of epoxy-modified polyurethane and novolac resins composites were investigated by using graphene oxide (GO) functionalized with hyperbranched poly(amidoamine) (PAMAM) as the curing component (GOD). The dendritic hybrid curing agent of GOD was synthesized via a divergent method and used to cure epoxy-terminated polyurethane (EPU) and epoxidized novolac resin (ENR). After preparation of the first generation of PAMAM dendrimer by using amino-functionalized GO as the core, Fourier transform infrared spectra, X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were used to prove the successful preparation method of GOD. TGA also showed that thermal characteristics of the hybrid EPU and ENR composites were determined by the amount of GOD and portion of the resins in the composites matrix. The hybrid composites with higher amounts of GOD and ENR matrix showed higher thermal stability and char residue. As example, the ENR-based hybrid composites with 3 wt% of GOD showed char residue of 57.2% at 600 degrees C and T-max of 401.2 degrees C. In addition, morphological and structural study of the graphitic and hybrid samples was investigated by XRD and electron microscopies.