Synthesis Of Novel Ni（Ⅱ） And Pd（Ⅱ）（Benzocyclohexan-ketoarylimino）₂and Their Catalytic Addition Copolymerization For Norbornene And Polar Monomers

To improve the performance of norbornene vinyl-addition polymer, the way ofcopolymer functionalization is a focus of the study, and the research of catalysts andcatalytic system is an important part. In this paper a series of Novel Ni(II) andPd(II)(benzocyclohexan-ketoarylimino)2(Ni{C10H8(O)C[2,6-C6H3(CH3)2N]CH3}2,C1; Pd{C10H8(O)C[2,6-C6H3(CH3)2N]CH3}2(C2) and Ni{C10H8(O)C[2,6-C6H3Cl2N]CH3}2(C3)) were synthesized and characterized by single crystal X-ray diffractionsfor the structures of them, respectively. Homo-and copolymerization of norbornene(NB) and polar monomers (5-norbornene-2-carboxylic acid methyl ester (NB-COOCH3), n-butyl methacrylate (n-BMA)) carried out in toluene by the catalysts ascatalyst precursors respectively, and tris(pentafluorophenyl)borane [B(C6F5)3] asunique co-catalyst. The influence of the different metal centers, the types ofsubstituent of N-aryl group, the effect of different monomer structure and feed ratioon the catalytic active, structures and properties of the outcomes.Homopolymerization of NB were implemented in toluene with the catalyticsystems of C1/B(C6F5)3, C2/B(C6F5)3and C3/B(C6F5)3, respectively. Both of themshown high catalytic activity (105), and the catalytic activity of Ni(II)/B(C6F5)3system was higher than that of Pd(II)/B(C6F5)3system.Under the reaction conditions of homopolymerization of NB, copolymerizationof NB/NB-COOCH3were implemented with the catalytic systems of C1/B(C6F5)3,C2/B(C6F5)3and C3/B(C6F5)3, respectively. The catalytic activity of C1/B(C6F5)3andC3/B(C6F5)3were high, and the orders of magnitude can be as high as105, butC1/B(C6F5)3catalytic systems higher than C3/B(C6F5)3. May be attribute to the-CH3or-Cl on N-aromatic ring, which existed different space steric hindrance andelectronic effect. The influence of catalyst structure and monomer feed ratio oncatalytic activity, conversion rate, chain structure and properties of outcomes. Filmsof these copolymers were obtained by THF solution casting method, and presentedgood translucency in the uv-vis range, and mechanical properties were improved.According to Kelen-Tüd s method, reactivity ratios of co-monomers were estimated, rNB-COOCH3=0.5，rNB=0.72, rNB·rNB-COOCH3=0.36, and constant ratio is0.625under thecatalytic system of C1/B(C6F5)3catalytic systems. The catalytic activity ofNi(II)/B(C6F5)3systems was higher than that of Pd(II)/B(C6F5)3systems, and thepolymers obtained by Ni(II)/B(C6F5)3possessed good performance compared withobtained by Pd(II)/B(C6F5)3.Copolymerization of NB/n-BMA were carried out by catalytic systems ofC1/B(C6F5)3and C3/B(C6F5)3, and both of them exhibited high activity. It’s possiblethat there was a catalytic deactivation mechanism of polymerization. Influence ofcatalyst structure on reactivity ratios of comonomer, catalytic activity, conversion rate,chain structure and properties of outcomes. Reactivity ratios of co-monomers wereestimated by Kelen-Tüd s method, reactivity ratios were rn-BMA=0.04, rNB=18.3asC1/B(C6F5)3for catalytic systems, and reactivity ratios were rn-BMA=0.29and rNB=3.28as C3/B(C6F5)3for the catalytic systems.