The effect of carbon black reinforcement on the dynamic fatigue and creep of polyisobutylene-based biomaterials

This paper investigates the structure-property relationship of a new generation of poly(styrene-b-isobutylene-b-styrene) (SIBS) block copolymers with a branched (dendritic) polyisobutylene core with poly(isobutylene-b-para-methylstyrene) end blocks (D_IBS), and their carbon black (CB) composites. These materials display thermoplastic elastomeric (TPE) properties, and are promising new biomaterials. It is shown that CB reinforced the block copolymer TPEs, effectively delayed the oxidative thermal degradation of the D_IBS materials, and greatly improved their dynamic fatigue performance. Specifically, the dynamic creep of a CB composite was comparable to that of chemically crosslinked and silica-reinforced medical grade silicone rubber, used as a benchmark biomaterial.