Tunable thermal degradation and refractive index of poly(norbornene sulfone)s via two different polymerization methods

A novel polysulfone was easily synthesized by alternating copolymerization of norbornene with sulfur dioxide (SO 2 ) via free radical copolymerization and coordination copolymerization. Compared with other olefin derivatives, norbornene is a cyclic olefin having a larger steric hindrance, which is easily copolymerized with SO 2 , and the obtained poly(norbornene sulfone)s have excellent thermomechanical and optical properties. The effect of the different polymerization methods on the copolymerization reaction was analyzed in detail. The results suggested that different polymerization mechanisms exist in the different polymerization methods and affect the thermal stability and optical properties of the polysulfone. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44534.