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以Ni(COD)2和含磷、氧配体为催化剂,利用乳液聚合法合成了间规聚苯乙烯.对产物进行了13 C-NMR、1 H-NMR、GPC、TEM、DSC、TG等表征.在此反应体系下,最佳聚合条件为:乳化剂用量为1.50 g,[St]0=1.79 mol.L-1,T=60℃,t=2 h,[Ni(COD)2]=1.102 mmol.L-1,转化率达78%,催化剂活性为662.14 g PS.(gNi.h)-1.粒度分析与TEM表明乳胶粒大小为100～120 nm.GPC分析表明重均分子量Mw可达1.64×106,数均分子量Mn可达9.79×105,分子量分布为1.6.在376℃下,聚苯乙烯具有很好的热稳定性,其玻璃化转变温度(Tg)为114.95℃.13C-NMR、1H-NMR及TG证实了产物的间规结构.通过对聚合反应动力学的初步研究,得到了聚合反应的表观活化能Ea为20.76 kJ/mol,速率方程:Rp=1.687×[St]0.241[Ni(COD)2]0.542([St]≤1.79 mol.L-1时),Rp=0.036 83×[St]-0.187[Ni(COD)2]0.542([St]>1.79 mol.L-1时).
Syndiotactic polystyrene was synthesized by emulsion polymerization using Ni (COD) 2 and phosphorus and oxygen ligands as catalysts, and the products were characterized by 13 C-NMR, 1 H-NMR, GPC, TEM, DSC and TG Under the optimum reaction conditions, the optimal conditions were as follows: the amount of emulsifier was 1.50 g, [St] 0 = 1.79 mol·L-1, T = 60 ℃, t = 2 h, = 1.102 mmol.L-1, the conversion rate was 78%, the catalyst activity was 662.14 g PS. (GNi.h) -1. The particle size analysis and TEM showed that the particle size of the latex was 100 ~ 120 nm .GPC analysis showed that the weight average molecular weight Mw Up to 1.64 × 106, the number average molecular weight Mn up to 9.79 × 105, the molecular weight distribution of 1.6 at 376 ℃, polystyrene has good thermal stability, the glass transition temperature (Tg) of 114.95 ℃ .13C The results showed that the apparent activation energy Ea of the polymerization reaction was 20.76 kJ / mol and the rate equation was Rp = 1.687 × [ Rp = 0.036 83 × [St] -0.187 [Ni (COD) 2] 0.542 ([St]> 1.79 mol .L-1).