Viscoelastic behavior of fullerene end-capped linear polymers

Viscoelastic behavior of C60-end-capped linear polybutadiene and C60-end-capped poly(butadiene-co-styrene) with molecular weight (Mn) ranging from 30 to 130 kg/mol and with polydispersity index (Mw/Mn) ranging from 1.02 to 1.08 was investigated. These polymers were synthesized through anionic polymerization of butadiene and styrene in hexane, in which the living ends were capped with the C60 via an alcoholate bridging. Rheological measurements showed that the polymer dynamics in the terminal zone were profoundly affected by the presence of fullerene, while the dynamics in the entanglement-plateau and at the terminal relaxation were nearly unaffected.