Characterization Of Silane-Functionalizaed Graphene Oxide And Preparation Of Polyurethane Matrix Nanocomposites

Graphene, a monolayer of carbon atoms packed into a dense honeycomb crystal structure,was very stable. Due to the unique structure, graphene has many excellent performances,which makes materials based on graphene show promising applications in electronics, energystorage, catalysis, optics, sensors etc. In this study, grphene oxide was prepared by theultrasonic of graphite oxide, which was prepared by the Hummers method. Then, grapheneoxide was functionalized by KH570to improve the compatibility of graphene oxide withorganic solvents and polyurethane. Finally, the functional graphene/polyurethane nanopositeswas synthesized by in situ method, and the obtained nanocomposites were characterized by aseries of characterization methods. The study is mainly focused on:(1) Graphene oxide and functional graphene were synthesized. The analysis results ofSEM and TEM showed that most of the graphene oxide and functional graphene weremonolayer. The results of TGA/DTG and contact angle measurement showed that thehydrophilic decreased and the lipophilicity increased after graphene oxide functionalized byKH570.(2) The solubility of graphene oxide in organic solvents was observed. It was found outthat the good solvents must meet the following conditions: the suface tension was between25and45mJ/m2, the solubility parameter δTwas between17.8and28.9MPa1/2, the dispersiveHansen parameter was between15.6and19.0MPa1/2, the polar Hansen parameter wasbetween5.7and16.6MPa1/2and the H-bonding Hansen parameter was between7.2and18.2MPa1/2. Besides, it was observed that the dispersions of graphene were according toLambert-Beer Law, and the extinction coefficient of graphene oxide was219.4L·g-1·m-1.(3) The functional graphene/polyurethane nanoposites was synthesized by in situ method,and the obtained nanocomposites were characterized by a series of characterization methods.The results of SEM showed that functional graphene was uniformly dispersed in polyurethaneresin. The results of TGA showed that the heat resistance of polyurethane resin increased byadding functional graphene. And the coating performance test results showed that thenanocomposites with0.5%functional graphene had the best performance. Compared withpolyurethane, impact strength, pencil hardness water resistance, acid resistance, and alkaliresistance of the nanocomposites with0.5%functional graphene increased dramatically.