Morphology, thermal stability, and mechanical behavior of [poly(propylene)-grafted maleic anhydride]-layered expanded graphite oxide composites

PP-g-MA-layered EGO composites were prepared directly by solution blending. Two types of PP-g-MA/EGO composites were prepared using different mixing methods: distributive and dispersive. In this study, the effects of the mixing method of EGO on the crystalline structure and thermo-mechanical properties of PP-g-MA/EGO composites are reported. WAXD exhibited a shift in 2 theta of the monoclinic (alpha) phase of PP-g-MA and (002) EGO peaks for PP-g-MA/EGO layered composites, which indicated a modification of the crystalline structure of PP-g-MA in the layered composites. DSC exhibited a single characteristic melting peak of monoclinic (alpha) crystalline phase PP-g-MA. The incorporation of EGO increased T-c indicating that the EGO acted as a nucleating agent for PP-g-MA. The crystallinity of the PP-g-MA/EGO composites was found to be dependent on the mixing method. Thermogravimetry demonstrated that PP-g-MA in the presence of EGO has higher degradation temperature, suggesting that the graphite particles acted as a thermal barrier material for PP-g-MA. DMA indicated that incorporation of EGO into PP-g-MA increased the storage modulus, due to the hydrogen bonding between EGO and MA of PP-g-MA.