后过渡金属苊基α-二亚胺镍催化剂的合成及催化降冰片烯聚合

Synthesis of acenaphthy-based Nickel(Ⅱ)-α-diimine complexes and norbornene polymerization

合成了2 种苊基α-二亚胺镍后过渡金属催化剂[ArN=C（Nap）-C（Nap）=NAr]NiBr2（Ar=2,6-（i-Pr）2-phenyl, Nap=5-R-1,8-naphthdiyl; 其中,Cat.1： R=H; Cat.2： R=OCH3）]. 考察了聚合体系在不同温度、铝镍化条件下对降冰片烯聚合反应活性的影响,并对聚合产物的红外光谱、1H-NMR 谱图及热稳定性进行分析. 结果表明：在以甲苯作溶剂、铝镍摩尔比为1 500、反应时间为1 h 的条件下催化剂具有最高的催化活性,未取代的催化剂（Cat. 1）在50 ℃时催化活性为4.61×10^4 g/（mol·h）,而甲氧基取代的苊基α-二亚胺镍（Cat. 2）在60 ℃时催化活性达到8.11×10^4 g/（mol·h）;红外谱图及1H-NMR 谱图表明2 种催化剂催化降冰片烯聚合均以加成聚合方式进行;Cat.2催化聚合产物具有更高的热稳定性.

Twoα-diimine nickel complexes [Ar-N=C (Nap)-C (Nap)=N-Ar]NiBr2 with different alkyl substituents on backbone carbon of acenaphthene [Ar=Ar=2,6-(i-Pr)2-phenyl, Nap=5-R-1,8-naphthdiyl;Cat.1:R=H;Cat.2:R=OCH3] were synthesized successfully. The effects of different conditions (substituents on the temperature changes, the new nickel catalyst and co-catalyst methylaluminoxane (MAO) content ratio, and acenaphthene carbon skeleton) on norbornene polymerization activity were observed. In toluene as a solvent, the reaction time was 1 h, the catalytic system had the highest activity when Al/Ni molar ratio was 1 500. The ethylene polymerization activities with Cat. 1 reached 4.61×104 g/(mol·h) under the condition 60℃ and those with Cat.2 reached 8.11×104 g/(mol·h) under 60℃ with Cat.2. IR and 1H-NMR showed that the norbornene polymerization was addition polymerization catalyzed by these two catalysts and the product catalyzed with Cat.2 showed higher thermal stability.