Fast, Efficient, Catalyst-Free Epoxidation of Butyl Rubber Using Oxone/Acetone for Improved Filler Dispersion.

Incorporation of a polar filler such as silica into a nonpolar rubber matrix is challenging and energy consuming due to their large difference in polarity. Epoxidation of carbon-carbon double bonds in unsaturated rubber, especially for rubber with low unsaturation such as butyl rubber, is an effective method to introduce polar functional groups to the rubber macromolecules for better filler dispersion. Although different epoxidation reagents including hydrogen peroxide (HO), peracid, and meta-chloroperoxybenzoic acid (mCPBA) have been previously reported, these reagents have different drawbacks.