The Liquefaction Of Graphene Oxide And Application Of Graphene Fluid In Rubber Composites

Graphene is a kind of material with sp2carbon atoms arranged in a honey comb lattice. As thethinnest material in the world, graphene has received extensive attention due to its excellentproperties, such as exceptional mechanical properties, outstanding electrical conductivity andthermal conductivity etc.In the present thesis, we used natural graphite as the raw material to prepare grapheneoxide (GO) through oxidization by strong acids. Then we used two different kinds of methodsto modify the GO, followed by grafting with polyetheramine to obtain two kinds ofsupramolecular ionic liquids based on graphene oxide (GO-SIL). The GO-SIL was furtherreduced into graphene based SIL (G-SIL). The G-SIL was used to modify the dispersion of aSBR/silica composite. The effects of the SIL on the dispersion and properties of thecomposites were studied. The main contents include the following three aspects.(1) Through the addition between the epoxy groups on GO and amine groups on sodiumsulfanilate, sulfonated graphene oxide (SGO) was prepared. Then Jeffamine2070wasadded to form ionic bond between sulfo groups of SGO and amine groups of Jeffamine2070and consequently the S-GOSIL was resulted. The rheological measurements on theS-GOSIL confirmed its viscoelasticity and the liquid-like behavior. The great influence ofionic bonding on the crystallization process of Jeffamine was also revealed. Its goodsolubility in both aqueous and organic solvents substantiated its amphiphilicity.(2) Via the reaction bewween GO (epoxy and hydroxyl groups) and sodium chloroacetate,carboxylated GO (CGO) was prepared. Then Jeffamine2070was introduced to form ionicbond between carboxyl groups and amine groups. Similarily, the rheologicalmeasurements confirmed its liquid-like behavior and viscoelasticity. The DSC resultsshowed that the ionic bond exhibited hindrance effect on the crystallization process ofJeffamine2070.(3) As an example of the application of the SIL, we attempted to used SIL as the dispersantagent for rubber composites. GO-SIL was firstly reduced into graphene based SIL (G-SIL).Then the SIL was added into a SBR/silica compound during open milling. The results showed that by adding only0.2phr of G-SIL to the SBR/silica, the dispersion of silica inthe rubber matrix could be effectively improved. Due to the reinforcing capability ofgraphene sheets and the presence of the surrounding Jeffamine oligomers, thesubstantially increased tensile strength and deformability of the composite wereconcurrently observed.