Catalytic ethylene polymerisation in carbon dioxide as a reaction medium with soluble nickel(II) catalysts.
نویسندگان
چکیده
A series of neutral Ni(II)-salicylaldiminato complexes substituted with perfluorooctyl- and trifluoromethyl groups, [Ni{kappa(2)-N,O-6-C(H)==NAr-2,4-R'(2)C(6)H(2)O}(Me)(pyridine)] (6 a: Ar=2,6-{4-(F(17)C(8))C(6)H(4)}(2)C(6)H(3), R'=I; 6 b: Ar=2,6-{4-(F(3)C)C(6)H(4)}(2)C(6)H(3), R'=I; 6 c: Ar=2,6-{3,5-(F(3)C)(2)C(6)H(3)}(2)C(6)H(3), R'=3,5-(F(3)C)(2)C(6)H(3); 6 d: Ar=2,6-{4-(F(17)C(8))C(6)H(4)}(2)C(6)H(3), R'=3,5-(F(3)C)(2)C(6)H(3); 6 e: Ar=2,6-{3,5-(F(3)C)(2)C(6)H(3)}(2)C(6)H(3), R'=I) were studied as catalyst precursors for ethylene polymerisation in supercritical CO(2). Catalyst precursors 6 a and 6 c, which are soluble in scCO(2), afford the highest polymer yields, corresponding to 2 x 10(3) turnovers. Semicrystalline polyethylene (M(n) typically 10(4) g mol(-1)) is obtained with variable degrees of branching (11 to 24 branches per 1000 carbon atoms, predominantly Me branches) and crystallinities (54 to 21 %), depending on the substitution pattern of the catalyst.
منابع مشابه
Thio-Pybox and Thio-Phebox complexes of chromium, iron, cobalt and nickel and their application in ethylene and butadiene polymerisation catalysis.
A series of bis(thiazolinyl)- and bis(thiazolyl)pyridine Thio-Pybox ligands and their metal complexes of chromium(III), iron(II), cobalt(II) and nickel(II) has been prepared, as well as a nickel(II) complex containing a monoanionic bis(thiazolinyl)phenyl Thio-Phebox ligand. These new metal complexes have been characterised and used as catalysts, in combination with the co-catalyst MAO, for the ...
متن کاملCatalytic Decomposition of Methane and Ethylene into the Carbon and Hydrogen
The role of nickel as catalyst on the conversion of methane and ethylene in a gas phase flow reactor in the absence of oxygen is studied. In this study, nickel in its different forms is used as catalyst. The role of pressure, flow rate, and temperature on the conversion of feed gases is investigated. The experiments have been carried out in the presence and absence of the catalysts to measure t...
متن کاملA comparative study on the kinetics of carbon dioxide methanation over bimetallic and monometallic catalysts
In this paper, Ni/Al and La-Ni/Al catalysts were prepared with a co-impregnation method and employed in carbon dioxide methanation reaction. The catalytic results showed that the catalyst with (10wt.%) of lanthanum and (20wt.%) nickel had the highest activity at low temperatures in CO2 methanation and the La-Ni/Al catalysts changed the reaction path by lowering its activation energy and consequ...
متن کاملEffect of MgAl2O4 catalyst support synthesis method on the catalytic activity of nickel Nano catalyst in reverse water gas shift reaction
In this research effect of synthesis method of magnesium aluminate as support of Ni catalysts at the reverse water gas shift (RWGS) reaction was evaluated. The RWGS reaction is applied in Carbon Dioxide Hydrogenation to Form Methanol via a Reverse Water-Gas Shift Reaction (CAMERE) process for the transformation of CO2 into methanol. The MgAl2O4 supports were prepared by sol-gel (M1), surfactant...
متن کاملCopolymerization of Ethylene and 1-olefins in Supercritical Co2 by an Electron Poor Ni(ii) Complex
SUPERCRITICAL CO2 BY AN ELECTRON POOR NI(II) COMPLEX Damien Guironnet and Stefan Mecking* Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, Germany. Introduction Late transition metal catalysts for polymerization of olefins have been studied intensely. Due to their functional group tolerance, polymerizations can be carried out in oxygenated reaction media, am...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Chemistry
دوره 12 23 شماره
صفحات -
تاریخ انتشار 2006