双-(β-酮萘胺)镍(Ⅱ)/MAO催化剂体系催化苯乙烯聚合

Polymerization of Styrene Catalyzed by Bis-(β-ketonaphthylamino) Nickel(Ⅱ)/MAO Catalyst System

采用双-(β-酮萘胺)镍(Ⅱ)为主催化剂,以甲基铝氧烷(MAO)为助催化剂,在甲苯溶剂中进行了苯乙烯聚合实验,并考察了聚合温度、Al/Ni摩尔比、单体浓度和聚合时间等因素对聚合反应的影响.结果表明,双-(β-酮萘胺)镍(Ⅱ)/MAO催化剂显示出很高的催化活性,可催化苯乙烯聚合得到中等分子量和分子量分布较窄(Mw/Mn<1.6)的聚苯乙烯.采用核磁共振氢谱、核磁共振碳谱、傅里叶变换红外光谱、差示扫描量热法和广角X射线衍射技术对聚合产物进行了表征.结果表明,所得聚合物为无规聚苯乙烯.

Polymerization of styrene was catalyzed by a new late transition metal complex catalyst system based on bis-（β-ketonaphthylamino） nickel（Ⅱ）/MAO （methylaluminoxane）. The influence of polymerization condi tions such as polymerization temperature, Al/Ni molar ratio, monomer concentration, and polymerization time was investigated. The obtained polymer was characterized by gel permeation chromatography, proton and ^13C nuclear magnetic resonance, Fourier transform infrared spectroscopy, differential scanning calorimetry, and wide-angle X-ray diffraction. The results indicated that the catalyst system exhibited high catalytic activity. The structure analysis result of the polymer demonstrated that the above catalyst system initiated styrene to yield atactic polystyrene with moderate molecular weight and narrow molecular weight distribution （Mw/Mn〈 1.6）.