| 摘要 |
1329334 Waxy ethylene polymers MITSUI PETROCHEMICAL INDUSTRIES Ltd 28 May 1971 [29 May 1970 30 May 1970 (2)] 18031/71 Heading C3P Waxes, i.e. polymers having a viscosity average molecular weight of 400 to 20,000 and a softening point of 80-135‹ C. (other physical properties being specified) are obtained by polymerizing ethylene in the presence of hydrogen and optionally an α-olefin, in solution in a saturated hydrocarbon diluent or in the molten wax itself, using a catalyst comprising (a) a halogen compound of titanium or vanadium supported on a hydrocarbon-insoluble magnesium compound, and (b) an organoaluminium compound, the amount of aluminium in component (b) being 1-100 atoms per atom of Ti or V and being 0À01 to 10 milliequivalents per litre of polymerization solvent. The polymerization is carried out at a temperature at which the wax is molten and a pressure of 20-100 kg/cm.<SP>2</SP> gauge when a hydrocarbon solvent is used or 5-100 kg./cm.<SP>2</SP> when the solvent is molten wax. The molar composition of the vapour phase, excluding solvent vapour, is 3-90% hydrogen, 0-35% α-olefin and the remainder ethylene. The catalyst carrier may be activated by treatment with a Lewis base (ethanol being exemplified) before treatment with the Ti or V compound. Exemplified catalysts are (a) TiCl 4 or VOCl 3 supported on MgO, Mg(OH) 2 , hydrated or anhydrous MgCl 2 , or coprecipitated MgO-Al 2 O 3 , with (b) Et 3 Al or i-Bu 3 Al. Continuous polymerization of ethylene, alone or in the presence of propylene or butene-1, in hexane is described. The waxes may be modified by oxidation, preferably by passing air through the molten wax at 130-200‹ C., and the oxidized products may be reacted with maleic acid or its derivatives, e.g. the dimethyl or dioctyl ester or the anhydride. |
