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Chapter 1 General Introduction Chapter 2 Living Polymerization of Lactones Catalyzed by Rare Earth Metal Alkyl Complexes. Chapter 3 Living Polymerization of Lactones Catalyzed by Rare Earth Metal Alkoxide Complexes. Chapter 4 Polymerization of Methyl Methacrylate Catalyzed by Rare Earth Metal Enolate Complexes. Chapter 5 Living Polymerization of Trimethylsilyl Substituted Methacrylate Catalyzed by Rare Earth Metal Complexes.

The steam invigoration of pitches (softening points 85 and 280 °C) homogenized with 1−3 wt % of organo rare-earth metal complexes such as Ln(C5H5)3 or Ln(acac) (Ln = Y, Yb) at 930 °C provided activated carbons with an extremely high mesopore ratio, >70%. The resulted activated carbon selectively adsorbs giant molecules such as vitamin B12, blue acid 90 dye, dextran, nystatin, and humic acid, reflecting their large mesopore volumes. To understand what kind of carbon skeleton in pitch is suited for generation of high mesopore ratio, the steam invigoration of a series of condensed polynuclear aromatics (COPNA) resins prepared from naphthalene, anthracene, phenanthrene, pyrene, or perylene and p-xylene-α,α‘-diol were conducted in the presence of rare-earth metal complexes. As a result, COPNA resins containing phenanthrene, perylene, and pyrene generated large mesopore volume.

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Block copolymerizations of ethylene or propylene with polar monomers remain an ultimate goal in polyolefin engineering since these processes promise to endow hydrophobic polymeric materials with remarkably high adhesive, dyeing, and moisture absorption properties. Although random copolymerizations of olefins with methyl methacrylate (MMA)1 or vinyl acetate2 have been put to practical use as an amendment process, this traditional technique possesses only a limited utility because it produces elastomers with variable composition only under drastic conditions (high temperature and high pressure).

Iron-terpyridine complexes, [Fe(terpyridine) 2](FeCl4)2 (1), FeCl3(terpyridine) (4), and FeCl3-(4,4′,4′′-tri-tert-butylterpyridine) (5), were found to display high catalytic activities for 1,2/3,4-polymerizations of isoprene and trans-1,4-polymerization of 1,3-butadiene in the presence of MMAO (modified methylalumoxane), whereas FeCl2(6,6′′-diarylterpyridine) complexes 2 and 3 exhibit no catalysis for polymerizations of these two monomers even in the presence of MMAO. The N,N,O-ligated N-(2-pyridyl)methyl-2-hydroxy-3,5-di-tert-butylbenzaldimine complex (6) of FeCl2 and the corresponding N-(2-pyridyl)-2-oxy-3,5-di-tert-butylbenzaldimine/FeCl (7) revealed more efficient catalysis for polymerization of isoprene and 1,3-butadiene. In sharp contrast to these N,N,N-donor or N,N,O-donor ligated complexes, N,N-ligated FeCl 2(sparteine) complex 8 shows much lower catalytic activities, although the stereospecifity is much higher.