Surface Modification of Layered Double Hydroxides for Reinforcement in Nitrile Butadiene Rubber

Abstract

This study examines the reinforcement of the nitrile butadiene rubber (NBR) composites with Zinc-aluminium layered double hydroxides (LDH) with sodium dodecyl sulfate (SDS) to enhance filler-matrix compatibility and mechanical properties. The pure LDH was prepared by the co-precipitation method, after which modification was done on the surface by the SDS, to enhance the hydrophobicity and interfacial contact with NBR. The successful intercalation of the SDS and increased basal spacing in the modified LDH were verified by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Tensile tests on the modified and unmodified LDH-NBR composites showed that SDS modification had a significant enhanced dispersion behavior of the filler, which resulted in an enhancement of mechanisms. The force- elongation curves exhibited linear behavior to some elongation after which there was sudden material failure, which was regarded as tensile limits of the composite. Even though, the SDS-modified LDH-NBR composites exhibited better reinforcement than the unmodified systems, unexpected failure in higher elongations indicated that additional optimization is necessary in filler dispersion and bonding between phases. The study has given a valuable insight into the potential of SDS-modified LDH as a reinforcing agent in NBR composites, with future studies aiming to optimize the filler dispersion, investigate alternative methods of modification, and evaluate the long-term performance within different environmental conditions.