Immobilization of Ti(OⁱPr)₄ onto silicon oxide surfaces and surface‐initiated polymerization of ϵ‐caprolactone

Controlled ring‐opening polymerization of ε‐caprolactone using polymer‐supported scandium catalyst

“…From that perspective, a solid-supported system is very important. Although some metal complexes might be grafted onto a silica or alumina support, 13,[20][21][22][23] the regeneration and recycle was unsuccessful. 20 From the perspective of green chemistry, further development of a recoverable polymer-supported catalyst is desired.…”

Novel Dinuclear Half‐Titanocene‐Producing Styrene/Ethylene Copolymers Containing Syndiotactic Styrene/Styrene Sequences

“…A wide variety of oxo-bridged titanium organometallic complexes have been reported to function as materials for photovoltaic applications, [27] as catalysts for ring-opening polymerizations, [28][29][30] and as photocatalyst materials. [31] Generally, the synthesis of titanium dinuclear complexes, containing more than two different bridging groups including an oxo-bridging group, is extremely difficult because the highly oxophilic nature of Ti metal causes the generation of oxo-bridged di-or multinuclear titanium complexes.…”

Production of Ultrahigh‐Molecular‐Weight Polyethylene/Pristine MWCNT Composites by Half‐Titanocene Catalysts

“…The EDS spectra showed the existence of half-titanocenes in the formed precatalysts: the Ti K a peak was observed at 4.56 keV for 1 and 2, and the Cl K a peak at 2.63 keV for 1 and at 2.66 keV for 2, respectively (see Supporting Information (SI)). The XPS data (see SI) also showed Ti peaks at 458.2 eV (Ti 2p3/2) and 463.9 eV (Ti 2p 1/2 ) for 1, and at 458.5 eV (Ti 2p 3/2 ) and 463.9 eV (Ti 2p 1/2 ) for 2, [26] indicating successful immobilization of the half-titanocenes onto the MWCNTs. After activation of the precatalysts with methylalumoxane (MAO), ethylene polymerization was carried out for 1 h with ethylene gas at a pressure of 1.01 Â 10 5 Pa. We obtained extremely high molecular weight (M w ) PEs from the 1/dried MAO system (M w ¼ 2 273 000 g mol À1 at polymerization temperature T p ¼ 30 8C, and M w ¼ 989 600 g mol À1 at T p ¼ 50 8C, Table 1).…”