Synthesis Of Fluorinated Bis-(β-ketoamino) Nickel (Ⅱ) And Modified Research By Catalytic Copolymerization Of Norbornene With Functional Monomer

The research of the copolymerization of norbornene and functional monomer catalyzed by late transition metal catalyst is an area of great recent interest in polyolefin material in order to improve the processability of polynorbornenes. Novel fluorinated catalyst Ni{CF3C(O)CHC[N(naphthyl)]CH3}2 was synthesized and the structure was solved by single crystal X-ray refraction technique in this paper, copolymerization of norbornene and n-butyl methacrylate, 1-alkene(1-hexene,1-octene,1-decene) catalyzed by fluorinated catalyst system Ni{CF3C(O)CHC[N(naphthy])]CH3}2 and non-fluorinated catalyst system Ni{CH3C(O)CHC[N(naphthyl)]CH3}2/B(C6F5)3 and copolymerization of norbomene and styrene, methoxycarbonylnorbornene catalyzed by fluorinated catalyst system Ni{CF3C(O)CHC[N(naphthyl)]CH3}2 were studied to investigate the effect of monomer structures on copolymer structures, properties and processabilities.Copolymerization of norbomene with n-butyl methacrylate were carried out with catalytic systems of bis-(β-ketoamino)nickel(II) complexes Ni{RC(O)CHC[N(naphthyl)]CH3}2 (R=CH3, CF3) and B(C6F5)3 in toluene. Both of the above catalytic systems exhibited higher activity for copolymerization of norbomene and n-butyl methacrylate. Influence of the comonomer feed content and catalyst structure on the yield and polymerization activity were investigated. The insertion mechanism including deactivation reaction on copolymerization of norbornene and n-butyl methacrylate catalyzed by bis-(β-ketoamino)nickel(II)/B(C6F5)3 catalytic systems was proposed. The reactivity ratios were determined by the Kelen-TUdOs method, and rn-BMA=0.095, rnbornene=12.626. Copolymer films were prepared and showed good transparency in the visible region.Copolymerization of norbornene with higher 1-alkene were carried out in toluene with catalytic systems based on nickel(Ⅱ) complexes Ni{RC(O)CHC[N(naphthyl)]CH3}2 (R=CH3, CF3) and B(C6F5)3 and exhibited high activity for both catalytic systems. Influence of the catalyst structure and comonomer feed content on the polymerization activity as well as on the incorporation rates were investigated. The reactivity ratios were determined to be rn-QCtcne=0.009 and rnrborniene=13.461 by the Kelen-TUdOs method for Ni{CH3C(O)CHC[N(naphthyl)]CH3}2/B(C6F5)3 system. The achieved copolymers were confirmed to be vinyl-addition copolymers through the analysis of 1H NMR and 13C NMR. TGA analysis results showed that the copolymers exhibited good thermal stability (Td> 400℃) and the glass transition temperature of the copolymers were observed between 215 and 275℃. The copolymers are confirmed to be noncrystalline by wide-angle X-ray diffraction (WAXD) analysis results and showed good solubility in common organic solvents.Copolymerization of norbornene (NB) with styrene (St) were carried out with catalytic system of Ni{CF3C(O)CHC[N(naphthyl)]CH3}2 and B(C6F5)3 in toluene. The catalytic system exhibited higher activity 1.37×105 (gpolymer/molNi·h) for copolymerization of norbornene and styrene. Influence of the comonomer feed content on the polymerization activity as well as on the incorporation rates were investigated. The styrene content in copolymers can be controlled to be 1.1-5.6 mol% at content of 10-50 mol% of the styrene in the monomer feeds ratios. The reactivity ratios were determined by the Kelen-TUdOs method, and rSt=0.453,rNB=19.810. The prepared copolymers had very high glass transition temperature (Tg> 320℃). Copolymers were processed by solution casting method and the films showed good transparency in the visible region with 75-80% transmittance.Copolymerization of norbornene (NB) with methoxycarbonylnorbornene (NB-COOCH3) were carried out with catalytic system of Ni{CF3C(O)CHC[N(naphthyl)]CH3}2 and B(C6F5)3 in toluene. The catalytic system exhibited higher activity 2.69×105(gpolymer/molNi·h) for copolymerization of norbornene and methoxycarbonylnorbornene. The influence results of the comonomer feed content on the polymerization showed that the NB-COOCH3 has a very high insertion ratio in all copolymers, and the NB-COOCH3 content in copolymers can be controlled to be 7.9-77.6 mol% at content of 10-90 mol% of the NB-COOCH3 in the monomer feeds ratios. The reactivity ratios were determined by the Kelen-TUdOs method, and rNB-COOCH3=0.578,rNB= 0.859. Copolymers were processed by solution casting method, dry/wet phase inversion technique and electrospinning respectively. The films prepared by solution casting method showed good transparency in the visible region. The membranes processed by dry/wet phase inversion technique were microporous structures. The fibers diameters fabricated by electrospinning were about 3μm.