Polyolefin-functionalized graphene oxide and its GO/HDPE nanocomposite with excellent mechanical properties

To prepare GO/Polyolefin nanocomposites with enhanced mechanical, electrical, or thermal properties is still a challenge due to the poor interfacial adhesion between GO and non-polar polyolefins. In this study, we report an effective strategy for the polyolefin-functionalized graphene oxide (fGO) using two-step methods GO was firstly modified by using glycidyl methacrylate (GMA) and styrene (St) dual monomers grafting method, thus GO-g-(GMA-co-St) with numerous epoxide groups is obtained. Then through the reaction between the epoxide group of GMA and anhydride group of maleic anhydrides (MAH) of the prepared HDPE-g-(MAH-co-St), GO-g-HDPE-g-(MAH-co-St) could be obtained. The successful preparation of the GO-g-HDPE-g-(MAH-co-St) was confirmed by AFM, TEM, FTIR, XRD, DSC, and TGA characterization. The results show the grafting ratios of the poly(GMA-co-St) and HDPE-g-(MAH-co-St) being up to 50.4 wt% and 70.4 wt%, respectively. The functionalized GO shows homogeneous dispersion in the nanocomposites with HDPE, and the stress at break and strain at break of the nanocomposite is increased by 28.7% and 130% respectively with only 0.2 wt% fGO loading. The approach of the polyolefin-functionalized GO paves a new way to develop not only polyolefin/graphene nanocomposites but also excellent nanocomposites of polyolefin/engineering plastic blends with graphene.