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Raman spectroscopy is well-known for its capability of detecting the physical properties, level of defects and number of layers for graphene-based materials, but far more than that, it's proven to be a versatile and promising tool for characterizing graphene-based polymer composites. This work focuses on the applications of Raman spectroscopy in the field of graphene-based polymer composites. The feature bands in Raman spectroscopy enable direct 2D and 3D imaging of graphene-based nanofillers in the polymer matrix, and even out of other carbonaceous materials. In addition, shifts in the vibrational frequencies of the characteristic bands induced by the strain of graphene could be utilized for analyzing the interactions between graphene-based nanofillers and polymer molecules, for calculating the effective moduli as well as for determining the spatial orientation of graphene-based nanofillers in the matrix. In the meantime, the recent progress of applications of Raman spectroscopy in the field of graphene-based polymer composites is introduced, such as the analysis of micromechanics of graphene-based nanocomposites, the investigation of stress transfer efficiency between the nanofillers and the matrix, and the reveal of key factors affecting material behavior. The Raman spectroscopy researches of graphene-based polymer composites currently are mainly focused on model composites, and the fluorescent effect of the matrix polymer as well limits the further applications of Raman spectroscopy. In order to address such problem, the amplified razor power are often adopted, and the resulted nonlinear effects are capable of increasing the intensity of the Raman signal, thus the Raman spectroscopy will be more widely applied in the field of graphene-based polymer composites.

Effect of low-melting-point curing agent (MOEA) on property of epoxy resin was studied. The properties of epoxy resin (MOEA40) with MOEA as the curing agent were characterized and compared with the epoxy resin (DDM30) with 4, 4'-diaminodiphenyl methane (DDM) as the curing agent. The viscosity-temperature property, curing behavior, mechanical properties and thermal properties were characterized by rotational rheometer, differential scanning calorimetry (DSC), universal material testing machine, dynamic thermomechanical analyzer (DMA) and thermal gravimetric analyzer (TGA), respectively. The results show that MOEA40 has better viscosity-temperature property than that of DDM30. MOEA shows low viscosity (0.2-3.5Pa·s) in the temperature range of 60-140℃. MOEA40 and DDM30 are cured with the same curing progressing. Cured MOEA40 shows outstanding mechanical properties with bending strength about 147MPa and tensile strength about 89 MPa, which are 9.7% and 11.2% higher than that of cured DDM30 (bending strength 134MPa, tensile strength 80MPa). In addition, cured MOEA40 shows higher glass transition temperature (168℃) and higher thermal stability with 5% mass loss temperature about 367℃ in nitrogen atmosphere.