Effect of Mercapto-Terminated Silane Treatment on Rheological and Mechanical Properties of Rice Bran Carbon-Reinforced Nitrile Butadiene Rubber Composites

This paper aims at correlating the silane treatment of rice bran carbon (RBC) in nitrile butadiene rubber (NBR) matrix with the rheological properties of RBC/NBR composites. The surface morphology and structure of RBC were characterized by X-ray diffraction, thermogravimetric analysis, high-resolution scanning electron microscopy (HR-SEM), Raman spectroscopy, and adsorption analysis. The RBC/NBR polymer-matrix composites were fabricated by using the latex compounding technique, based on the superior hydrophilic characteristics of RBC. The silane treatment process was conducted by in situ interfacial modification technique. The dispersion of RBC and the interfacial morphologies between the RBC and NBR matrix were confirmed by HR-SEM. The bonding mechanism was analyzed in detail by mechanical and dynamic rheological determinations. At the same filler concentration, the (3-mercaptopropyl) trimethoxysilane (MPTMS) treated composites exhibited stronger mechanical properties and higher storage modulus than original RBC/NBR composite, as the interfacial interaction via MPTMS connected RBC and NBR molecules was stronger than the interaction in RBC/NBR composites connected by hydrogen bonds and weaker π-π stacking.