.jpg)
Phthaldialdehyde and phthaldiketone were treated with substituted phenols of 2-amino-4-methylphenol, 2-amino-5-methylphenol and 2-amino-4-t-butylphenol, respectively, and then treated with transition metal halides of TiCl4, ZrCl4 and YCl3. A series of novel non-metallocene catalysts (1–12) with phenoxy-imine ligands was obtained. The structures and properties of the catalysts were characterized by 1H NMR and elemental analysis. The catalysts (1–12) were used to promote ethylene (co-)polymerization after activation by methylaluminoxane. The effects of the structures and center atoms (Ti, Zr and Y) of these catalysts, polymerization temperature, Al/M (M = Ti, Zr and Y) molar ratio, concentration of the catalysts and solvents on the polymerization performance were investigated. The results showed that the catalysts were favorable for ethylene homopolymerization and copolymerization of ethylene with 1-hexene. Catalyst 10 is most favorable for catalyzing ethylene homopolymerization and copolymerization of ethylene with 1-hexene, with catalytic activity up to 2.93 × 106 gPE (mol Y)−1 h−1 for polyethylene (PE) and 2.96 × 106 gPE (mol Y)−1 h−1 for copolymerization of ethylene with 1-hexene under the following conditions: polymerization temperature 50 °C, Al/Y molar ratio 300, concentration of catalyst 1.0 × 10−4 L−1 and toluene as solvent. The structures and properties of the polymers obtained were characterized by Fourier transform infrared spectroscopy, 13C NMR, wide-angle X-ray diffraction, gel permeation chromatography and DSC. The results indicated that the obtained PE catalyzed by 4 had the highest melting point of 134.8 °C and the highest weight-average molecular weight of 7.48 × 105 g mol−1. The copolymer catalyzed by 4 had the highest incorporation of 1-hexene, up to 5.26 mol%, into the copolymer chain. © 2012 Society of Chemical Industry
A series of novel nonmetallocene catalysts with phenoxy-imine ligands was synthesized by the treatment of phthaldialdehyde, substituted phenol with TiCl4, ZrCl4, and YCl3 in THF. The structures and properties of the catalysts were characterized by 1H NMR and elemental analysis. These catalysts were used for copolymerization of ethylene with acrylonitrile after activated by methylaluminoxane (MAO). The effects of copolymerization temperature, Al/M (M = Ti, Zr, and Y) ratio in mole, concentrations of catalyst and comonomer on the polymerization behaviors were investigated in detail. These results revealed that these catalysts were favorable for copolymerization of ethylene with acrylonitrile. Cat.3 was the most favorable one for the copolymerization of ethylene with acrylonitrile, and the catalytic activity was up to 2.19 × 104 g PE/mol.Ti.h under the conditions: polymerization temperature of 50 °C, Al/Ti molar ratio of 300, catalyst concentration of 1.0 × 10–4 mol/L, and toluene as solvent. The resultant polymer was characterized by FTIR, cross-polarization magic angle spinning, 13C NMR, WAXD, GPC, and DSC. The results confirmed that the obtained copolymer featured high-weight–average molecular weight, narrow molecular weight distribution about 1.61–1.95, and high-acrylonitrile incorporation up to 2.29 mol %. Melting temperature of the copolymer depended on the content of acrylonitrile incorporation within the copolymer chain. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
The star-shaped polymethylmethacrylate (PMMA) was synthesized via radical polymerization promoted by metallocene complexes in the presence of initiator of tetra(2,3-epoxy propoxy)silane (Is) and reducing agent Zn. The effect of temperature, time, molar ratio of monomer to initiator, and the structure of metallocene complexes on the polymerization performance was investigated. The structure and properties of the obtained polymer were characterized by gel permeation chromatography, multiangle laser light scattering, 1H NMR, 13C NMR, and WAXD. The results indicated that the obtained polymer was atacticspecific and featured narrow molecular weight distribution (1.30–1.57). Star-shaped organosiloxane-functionalized PMMA was produced. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The copolymerization of styrene with ethylene was promoted by CpTiCl3/BDGE/Zn/MAO catalyst system combining free radical polymerization with coordination polymerization via sequential monomer addition strategy in one-pot. The effect of polymerization conditions such as temperature, time, ethylene pressure, and Al/Ti molar ratio on the polymerization performance was investigated. The hydroxy-functionalized aPS-b-random copolymer-b-PE triblock copolymer was obtained by solvent extraction and determined by GPC, DSC, WAXD, and 13C-NMR. The DSC result indicated that the aPS-b-random copolymer-b-PE had a Tg at 87°C and a Tm at 119°C which attributed to the Tg of aPS segment and the Tm of PE segment, respectively. The microstructure of the hydroxy-functionalized aPS-b-random copolymer-b-PE was further confirmed by WAXD, 13C-NMR, and 1H-NMR analysis; and these results demonstrated that the obtained block copolymer consisted of aPS segment, S-E random copolymer segment, and crystalline PE segment. The connection polymerization of the hydroxy-functionalized aPS with random copolymer-b-PE was revealed by GPC results. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Well-defined comblike atactic polystyrene functionalized with hydroxyl groups was synthesized via living/controlling radical polymerization promoted by metallocene complexes in the presence of poly(phenyl glycidyl ether)-co-formaldehyde as the initiator and Sn as a reducing agent. The effect of the polymerization conditions, such as the ratio of initiator to monomer, temperature, and polymerization time, and the structure of the metallocene complex on the polymerization process were investigated. The resulting polymers were characterized by gel permeation chromatography, multiangle laser light scattering, 1H-NMR, and 13C-NMR. The results show that the polymer had a narrow molecular weight distribution in the range 1.1–1.4 and the number-average molecular weight of the polymer linearly depended on the monomer conversion within the polymerization timescale, which confirmed that living radical polymerization characteristics prevailed in the polymerization process. Both the number of arms and the number of hydroxyl groups in each polymer molecule were about four, which suggested that they arose from the epoxy functional groups of the initiator. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A series of novel bridged multi-chelated non-metallocene catalysts is synthesized by the treatment of N,N-imidazole, N,N-dimethylimidazole, and N,N-benzimidazole with n-BuLi, 2,6-dimethylaniline, and MCl4 (M = Ti, Zr) in THF. These catalysts are used for copolymerization of ethylene with 1-hexene after activated by methylaluminoxane (MAO). The effects of polymerization temperature, Al/M molar ratio, and pressure of monomer on ethylene copolymerization behaviors are investigated in detail. These results reveal that these catalysts are favorable for copolymerization of ethylene with 1-hexene featured high catalytic activity and high comonomer incorporation. The copolymer is characterized by 13C NMR, WAXD, GPC, and DSC. The results confirm that the obtained copolymer features broad molecular weight distribution (MWD) about 33–35 and high 1-hexene incorporation up to 9.2 mol %, melting temperature of the copolymer depends on the content of 1-hexene incorporation within the copolymer chain and 1-hexene unit in the copolymer chain isolates by ethylene units. The homopolymer of ethylene has broader MWD with 42–46. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 417–424, 2010
A kind of novel bridged nonmetallocene catalysts was synthesized by the treatment of N,N-imidazole and N,N-phenylimidazole with n-BuLi, and MCl4 (M = Ti, Zr) in THF. Those catalysts were performed for ethylene polymerization after activated by methylaluminoxane (MAO). The effects of polymerization temperature, Al/M ratio, pressure of monomer, and concentration of catalysts on ethylene polymerization behaviors were investigated in detail. Those results revealed that the catalyst system was favorable for ethylene polymerization with high catalytic activity. The polymer was characterized by 13C NMR, WAXD, GPC, and DSC. The result confirmed that the obtained polyethylene featured broad molecular weight distribution around 20, linear structure, and relative low melting temperature. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 33–37, 2008
The synthesis of syndiotactic polystyrene (sPS) catalyzed with Cp*Ti(OBz)3/MAO/TIBA and toluene as the solvent and the effects of polymerization temperature and the external addition of TIBA on polymerization behavior were investigated. The study revealed that catalytic activity increased with polymerization temperature. The greatest activity, 619 kg sPS mol−1 Ti h−1, was exhibited up to 90°C. TIBA also improved catalytic activity. The molecular weight of the polymer obtained decreased with polymerization temperature and the amount of TIBA. The structure and properties of syndiotactic polystyrene were characterized by 13C-NMR, FTIR, DSC, and GPC methods. It was confirmed that the sPS obtained featured all-trans planar zigzag conformation and higher syndiotacticity, molecular weight, and melting point. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 501–505, 2007
Oligomer of 1-decene was synthesized with Ziegler-Natta catalyst consisting of TiCl4, AlCl3, Et2AlCl, and SiO2 used as support. The effects of temperature, time, ratio of Al/Ti, and concentration of Ti on oligomerization behaviors were investigated. The results showed that the catalyst system was desirable for oligomerization of 1-decene with good catalytic activity, 153.4 kg oligomer/mol Ti h, under typical conditions. The oligomer obtained was characterized with GC–MS, GC, and 13C NMR methods. The results indicated that the oligomer was of a mixture consisting of di-, tri-, tetra-, and pentamer. The 13C NMR data also implied that chain propagation of this oligomer involved primarily head-to-tail 1, 2-insertions, as well as head-to-head and tail-to-tail 2, 1-insertions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 584–590, 2006
A novel catalyst precursor, the monotitanocene (η5-pentamethylcyclopentadienyl) titanium tricinnamyloxide [Cp*Ti(OCH2CHCHC6H5)3], was synthesized and employed for butene-1 polymerization in the presence of methylaluminoxane. The effects of the polymerization conditions on the catalytic activity, molecular weight, stereoregularity, and regioregularity of the polymer so obtained were investigated in detail. The results show that the monotitanocene is desirable for the production of atactic polybutene-1 coupled with good yields under typical polymerization conditions, high molecular weight (weight-average molecular weight = 5.3–9.6 × 105), and stereoirregularity with the Bernoullian factor B equal to 0.95, which indicates that chain-end control is predominant. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4068–4073, 2001
![Titanium,bis[(1,2,3,4,5-h)-1-butyl-2,4-cyclopentadien-1-yl]dichloro-](http://img.cochemist.com/ccimg/73400/73364-20-2.png)
![Titanium,bis[(1,2,3,4,5-h)-1-butyl-2,4-cyclopentadien-1-yl]dichloro-](http://img.cochemist.com/ccimg/73400/73364-20-2_b.png)
