Surface modification of silica with polymethylmethacrylate‐co‐methacrylic acid for enhancement of self‐healing performance of natural rubber composites based on metal thiolate ionic network

Abstract

AbstractPolymethylmethacrylate‐co‐methacrylic acid (PMMA‐co‐MAA) was utilized for surface improvement of silica to be used as reinforcement in self‐healing natural rubber based on metal thiolate ionic network. The amount of PMMA‐co‐MAA was varied at 1, 3, and 5 wt% of silica content and the optimized PMMA‐co‐MAA was utilized to investigate the self‐healing NR/silica composites at different filler loading (5, 10, 20, and 30 phr). The graft polymerization of PMMA‐co‐MAA on silica was confirmed using FTIR spectroscopy and grafting percentage was determined by thermogravimetric analysis (TGA). Intermolecular diffusion occurred at the fractured area was detected using a scanning electron microscope (SEM) and the results revealed that the composite tensile and tear performance increased 22%–70% with healing efficiency percentage ranging between 70% and 97% depending on the silica loading.