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A new catalyst composed of Tin|bridged yttrocene Ph-2Sn(MeCp)-2YCl (MeCp=methylcyclopentadienyl) and Al(i|Bu)-3 was successfully developed for the polymerization of methyl methacrylate(MMA). Detailed study of factors (such as the molar ratio of Al/Cat., catalyst concentration, various solvents, temperature and time) influencing polymerization reaction indicated that the catalytic active species may be still somewhat stable at high temperature and still have a long catalytic lifetime. {}+1H NMR spectrum showed about 65% syndiotactic content in the polymethyl methacrylate(PMMA) prepared. From kinetic studies, the polymerization rate equation may be expressed as Rp=Kp+{2.4}. The overall activation energy of polymerization is 20.9±3.1 kJ/mol.
A new catalyst composed of Tin | bridged yttrocene Ph 2Sn (MeCp) -2YCl (MeCp = methylcyclopentadienyl) and Al (i | Bu) - 3 was successfully developed for the polymerization of methyl methacrylate (MMA). Detailed study of factors (such as the molar ratio of Al / Cat., Catalyst concentration, various solvents, temperature and time) influencing polymerization reaction indicated that the catalytic active species may be still somewhat stable at high temperature and still have From kinetic studies, the polymerization rate equation may be expressed as Rp = Kp + {2.4 }. The overall activation energy of polymerization is 20.9 ± 3.1 kJ / mol.