Adv Polym Sci (2013) 258: 143–162
DOI: 10.1007/12_2013_211
# Springer-Verlag Berlin Heidelberg 2013
Published online: 11 May 2013
Trialkylaluminum-Free Modified
Methylaluminoxane as a Cocatalyst
for Living Polymerization of Olefins
Takeshi Shiono
Abstract This article reviews living polymerization of olefins with several
dimethyltitanium complexes by the use of trialkylaluminum-free modified
methylaluminoxane (dMMAO) as a cocatalyst. The excellent solubility of
dMMAO allows living coordination polymerization of olefins in aliphatic
hydrocarbons. A chelating diamidodimethyltitanium complex (1) conducted living
polymerization of propene in heptane at 0
C to produce atactic polymer. Metal
oxide-supported dMMAO was also effective as a cocatalyst for the controlled
polymerization of propene with 1, where the propagation rate and the molecular
weight distribution of the produced polymer were dependent on the metal oxide
used. ansa-Dimethysilylene(fluorenyl)(tert-butylamido)dimethyltitanium (2) activated
by dMMAO conducted living polymerization of propene at 0
C in chlorobenzene,
toluene and heptane. The propagation rate and the syndiotactic(syn)-specificity of the
catalyst were dependent on the solvent as follows: propagation rate, chlorobenzene >
toluene > heptane; syn-specificity, chlorobenzene < toluene < heptane. The propagation rate and the syn-specificity were also dependent on the substituent on the
fluorenyl ligand of 2, and a highly active and syn-specific living polymerization was
achieved by the use of a 3,6-di-tert-butyl substituted complex (4). Complex 2 and
its derivatives such as 4 activated by dMMAO also conducted living homo- and
copolymerization of norbornene and 1-alkene in toluene, which afforded a variety
of tailor-made polyolefins composed of norbornene and 1-alkene.
Keywords 1-Alkene Á Living polymerization Á Modified methylaluminoxane Á
Norbornene Á Propene Á Single-site catalyst Á Supported catalyst
T. Shiono (*)
Graduate School of Engineering, Hiroshima University, Kagamiyama 1-4-1,
Higashi-Hiroshima, 739-8527 Hiroshima, Japan
e-mail: tshiono@hiroshima-u.ac.jp
DOI: 10.1007/12_2013_211
# Springer-Verlag Berlin Heidelberg 2013
Published online: 11 May 2013
Trialkylaluminum-Free Modified
Methylaluminoxane as a Cocatalyst
for Living Polymerization of Olefins
Takeshi Shiono
Abstract This article reviews living polymerization of olefins with several
dimethyltitanium complexes by the use of trialkylaluminum-free modified
methylaluminoxane (dMMAO) as a cocatalyst. The excellent solubility of
dMMAO allows living coordination polymerization of olefins in aliphatic
hydrocarbons. A chelating diamidodimethyltitanium complex (1) conducted living
polymerization of propene in heptane at 0
C to produce atactic polymer. Metal
oxide-supported dMMAO was also effective as a cocatalyst for the controlled
polymerization of propene with 1, where the propagation rate and the molecular
weight distribution of the produced polymer were dependent on the metal oxide
used. ansa-Dimethysilylene(fluorenyl)(tert-butylamido)dimethyltitanium (2) activated
by dMMAO conducted living polymerization of propene at 0
C in chlorobenzene,
toluene and heptane. The propagation rate and the syndiotactic(syn)-specificity of the
catalyst were dependent on the solvent as follows: propagation rate, chlorobenzene >
toluene > heptane; syn-specificity, chlorobenzene < toluene < heptane. The propagation rate and the syn-specificity were also dependent on the substituent on the
fluorenyl ligand of 2, and a highly active and syn-specific living polymerization was
achieved by the use of a 3,6-di-tert-butyl substituted complex (4). Complex 2 and
its derivatives such as 4 activated by dMMAO also conducted living homo- and
copolymerization of norbornene and 1-alkene in toluene, which afforded a variety
of tailor-made polyolefins composed of norbornene and 1-alkene.
Keywords 1-Alkene Á Living polymerization Á Modified methylaluminoxane Á
Norbornene Á Propene Á Single-site catalyst Á Supported catalyst
T. Shiono (*)
Graduate School of Engineering, Hiroshima University, Kagamiyama 1-4-1,
Higashi-Hiroshima, 739-8527 Hiroshima, Japan
e-mail: tshiono@hiroshima-u.ac.jp