Preparation of Amphipathic Graphene Oxide/Poly(acrylic acid-methyl methacrylate) Composite Hydrogel and the Study on Its Tribological Property Under Media Regulation

In order to address the problem of poor mechanical strength of hydrogels in solvents and maintaining its property of low surface friction coefficient to meet the requirements for bio-lubrication materials, the amphipathic graphene oxide/poly(acrylic acid-methyl methacrylate) composite hydrogel which is enhanced by graphene oxide was prepared by one-step polymerization method in N,N-Dimethylformamide/pure water(DMF/H₂O) mixed solvent. The rheometer was used to test the mechanical property of composite hydrogel material. The results showed the hydrophobic content of PMMA polymer chains can significantly enhance the mechanical strength of composite hydrogel. Furthermore, by changing the ratios of hydrophilic-hydrophobic segments in composite hydrogel network as well as the DMF/H₂O mixed solvent respectively, the swelling and tribological properties of graphene oxide/poly(acrylic acid-methyl methacrylate) composite hydrogel were tested. The experimental results exhibited that the amphipathic composite hydrogel possesses obvious media responsive behavior so that the tunable friction property under different solvents can be realized.