Preparation of zinc oxide/halloysite compound and their reinforcement for styrene butadiene rubber composite

This study investigated the surface treatment of halloysite nanotubes (HNTs) with zinc oxide (ZnO) and used to enhance the mechanical properties of butyl rubber (SBR) composites. The prepared ZnO-modified HNTs (ZnO/HNTs) was characterized by X-ray diffraction (XRD), Fourier infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The results indicated that ZnO particles were successfully loaded on the surface of HNTs and interacted with hydroxyl groups. The outer surface of HNTs became rough due to the loading of ZnO. The effects of ZnO/HNTs on the processing and mechanical properties of filled SBR composites were evaluated. The results showed that the ZnO/HNTs particles displayed a fine dispersion in the matrix system and have a strong interaction compatibility with rubber matrix chains. The tensile strength reached at the maximum of 9.35 MPa at a filler content of 60 phr, which was 405% and 31.69% higher than those of pure SBR and the HNTs/SBR composites, respectively. The enhancement of the mechanical properties of filled SBR composites is attributed to the fine dispersion of the ZnO/HNTs particles in the SBR matrix and the improved incorporation between the rubber molecules and the filler particles due to the loading of ZnO on the surface of HNTs, which restricts the movement of the rubber chains by entrapping molecules when the composites is subjected to stress loading.