Styrene has been polymerized to syndiotactic polystyrene (sPS) over a layer of heterogeneous Cp*Ti(OCH₃)₃/MAO catalyst immobilized onto the surfaces of silica nanotube reactor (SNTR) arrays of 60–200 nm in diameter. The polymer produced in the SNTR arrays has been found to have the molecular weights much larger than the polymers synthesized by a liquid slurry polymerization over silica‐supported catalysts. A dynamic reactor model that consists of diffusion and reaction terms has been derived and solved to quantify the kinetics of styrene polymerization in a single nanotube reactor. The two‐site kinetic model applied to the silica nanotube reactor model shows that the experimentally observed high polymer molecular weight can be fitted if the chain transfer rate constants for monomer and β‐hydride elimination are reduced significantly. The simulation results suggest that the presence of dense crystalline sPS nanofibrils filling the nanotubes constrain the molecular movements of polymer chain ends in the proximity of catalyst sites to limit the chain transfer reactions. POLYM. ENG. SCI., 60:700–709, 2020. © 2020 Society of Plastics Engineers

中文翻译：

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二氧化硅纳米管反应器中非均相催化剂层上苯乙烯的几何约束聚合

苯乙烯已在非均相Cp * Ti（OCH ₃）₃层上聚合成间同聚苯乙烯（sPS）/ MAO催化剂固定在直径60-200 nm的二氧化硅纳米管反应器（SNTR）阵列的表面上。已发现在SNTR阵列中生产的聚合物的分子量比在硅胶负载的催化剂上通过液相淤浆聚合法合成的聚合物大得多。推导并求解了由扩散和反应项组成的动态反应器模型，以量化单个纳米管反应器中苯乙烯聚合的动力学。应用于二氧化硅纳米管反应器模型的两点动力学模型表明，如果单体和β-氢化物消除的链转移速率常数显着降低，则可以拟合实验观察到的高分子量聚合物。模拟结果表明，填充纳米管的致密结晶sPS纳米原纤维的存在限制了聚合物链末端在催化剂位置附近的分子运动，从而限制了链转移反应。POLYM。ENG。SCI。，60：700–709，2020.©2020塑料工程师协会