Post-Synthesis Backbone Modification of Polypentenamer Rubber and Related Tire Compositions

Rubber compounds may comprise: an epoxidized polypentenamer rubber (CPR) and/or a hydrolyzed epoxidized CPR; and a filler comprising silica particles. One nonlimiting example is rubber compound comprising: phr to 90 phr of a styrene-butadiene rubber (SBR), a natural rubber (NR), and/or a butadiene rubber (BR); 10 phr to 50 phr of a epoxidized CPR and/or a hydrolyzed epoxidized CPR; and 10 phr to 200 phr of a filler comprising silica particles, wherein the SBR, the NR, the BR, the epoxidized CPR, and the hydrolyzed epoxidized CPR combined equal 100 parts. Rubber compounds comprising epoxidized CPR and/or a hydrolyzed epoxidized CPR; and a filler comprising silica particles may be useful in tire compositions.