%0 Journal Article %A M. Wannaborworn and B. Jongsomjit and T. Shiono %D 2012 %J International Journal of Materials and Metallurgical Engineering %B World Academy of Science, Engineering and Technology %I Open Science Index 68, 2012 %T Effect of Substituent on Titanocene/MMAO Catalyst for Ethylene/1-Hexene Copolymerization %U https://publications.waset.org/pdf/5365 %V 68 %X Copolymerization of ethylene with 1-hexene was carried out using two ansa-fluorenyl titanium derivative complexes. The substituent effect on the catalytic activity, monomer reactivity ratio and polymer property was investigated. It was found that the presence of t-Bu groups on fluorenyl ring exhibited remarkable catalytic activity and produced polymer with high molecular weight. However, these catalysts produce polymer with narrow molecular weight distribution, indicating the characteristic of single-site metallocene catalyst. Based on 13C NMR, we can observe that monomer reactivity ratio was affected by catalyst structure. The rH values of complex 2 were lower than that of complex 1 which might be result from the higher steric hindrance leading to a reduction of 1- hexene insertion step. %P 816 - 818