Thermal, Mechanical Properties and Rheological Behavior of Poly(Propylene Carbonate)/Poly(Ethylene Glycol)/Graphene Oxide Nanocomposites

Graphene oxide (GO) is an efficient nanofiller for polymers and a good dispersion of GO in polymer matrix is most important to enhance properties. Poly(propylene carbonate) (PPC)/GO nanocomposite was prepared by a method with solution blending and melt mixing for improvement of GO dispersion. First, GO was prepared using an improved Hummers method. In the solution blending, GO was well dispersed in water and another low molecular weight polymer, poly(ethylene glycol) (PEG), was also dispersed in water, as a dispersion medium for next melt mixing of PPC and GO. Then PPC and PEG/GO was melt-mixed in a HAAKE mixer. The dispersion of GO in PPC matrix and effect of GO content on properties of PPC/PEG/GO nanocomposites was investigated. Results show that tensile strength of nanocomposites with the content of 0.5 wt% GO increased from 17.51 MPa (pure PPC) to 21.61 MPa and elongation at break can be kept high. The complex viscosity, storage and loss modulus is the highest for nanocomposites with the content of 0.5 wt% GO. This illustrated that a lower content of GO can improve the properties of PPC, owing to the good dispersion of GO in PPC matrix. Based on dispersion of GO and chemical structure of PPC, PEG, and GO, the reinforcement mechanism of GO in PPC was analyzed.