Effect of coupling agents and ionic liquid on the properties of rice bran carbon/carboxylated styrene butadiene rubber composites

Latex compounding method (LCM) was applied to ensure a better dispersion state of filler in rubber matrix. In order to enhance the compatibility and interfacial interaction between carboxylated-styrene butadiene rubber (XSBR) and rice bran carbon (RBC), a series of coupling agents i.e., N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AAPTS), 3-mercaptopropyltrimethoxysilane (MPTMS), 4,4-methylene bis(phenyl isocyanate) (MDI) and ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate (HMIMPF6) were applied. Morphology of the fracture surface, mechanical property, thermal stability, vulcanization characters and dynamic mechanical property were investigated. The characterization on the resultant composites demonstrated that the MDI exhibited the superior reinforcing effect, of which the tensile strength and 300% modulus reached to 16.43 and 16.33 MPa, respectively. The study on fracture surface, Raman spectrum, thermal stability and storage modulus confirmed the strong interfacial interaction resulted from MDI. In addition, ionic liquid also exhibited coupling activity, improving the mechanical properties of the composites.