Preparation and characterization of maleic anhydride-grafted desulfurization rubber powder by free-radical polymerization

The objective of the article was to enhance the recycling value of solid waste rubber by surface functionalization of desulfurized rubber powder using a one-pot method based on free-radical polymerization theory. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, scanning electron microscopy, and elemental analysis were used to characterize the maleic anhydride-grafted desulfurized rubber powder, and the grafting mechanism was also investigated. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirmed that maleic anhydride was grafted onto the desulfurized rubber powder. Thermogravimetric analysis indicated that the maleic anhydride-grafted desulfurized rubber powder and desulfurized rubber powder possessed different thermal properties and structure. The results of scanning electron microscopy and elemental analysis illustrated that the surface of the desulfurized rubber powder was covered with a layer of fold-like maleic anhydride polymer. The mechanism of grafting desulfurized rubber powder with maleic anhydride may be achieved by replacing the active α-H on the methylene group of the desulfurized rubber macromolecule chain.