Copolymerization of norbornene with styrene catalyzed by Ni{CF_3C(O)CHC[N(naphthyl)]CH_3}_2/B(C_6F_5)_3 and transparent films

摘要

Copolymerization of norbornene (NB) with styrene (St) was carried out with the catalytic system of Ni{CF_3C(O) CHC[N(naphthyl)]CH_3}_2 and B(C_6F_5)_3 in toluene. The catalytic system exhibited higher activity 1.37xl0~5 (g_(polymer)/ molNi-h) for copolymerization of NB and St. The influence of the comonomer feed content on the polymerization activity, as well as on the incorporation rates, was investigated. The St content in copolymers can be controlled to be 1.1-5.6 mol% at a content of 10-50 mol% of the St in the monomer feeds ratios. The reactivity ratios were determined to be r_(st)=0.453 and r_(NB)=19.810 by the Kelen-T(U)d(O)s method catalyzed by the Ni{CF_3C(O)CHC[N(naphthyl)]CH_3}_2/B(C_6F_5)_3 system. The prepared copolymers had very high glass transition temperatures (T_g>320℃). Copolymers were processed by the solution casting method and the copolymer films showed good transparency in the visible region with 75-80% transmittance.