摘要:
Catalyst component comprising Mg, Ti, and halogen atoms, and is characterized in that (a) the Ti atoms are present in an amount higher than 4% based on the total weight of the said catalyst component, (b) the amount of Mg and Ti atoms is such that the Mg/Ti molar ratio is higher than 2 and (c) by a X-ray diffraction spectrum, in which, in the range of 2θ diffraction angles between 47° and 52°, at least two diffraction lines are present at diffraction angles 2θ of 48.3±0.2°, and 50.0±0.2°, the most intense diffraction lines being the one at 2θ of 50.0±0.2°, the intensity of the other diffraction line being equal to or lower than the intensity of the most intense diffraction line.
摘要:
Catalyst component comprising Mg, Ti, and halogen atoms, and is characterized in that (a) the Ti atoms are present in an amount higher than 4% based on the total weight of the said catalyst component, (b) the amount of Mg and Ti atoms is such that the Mg/Ti molar ratio is higher than 2 and (c) by a X-ray diffraction spectrum, in which, in the range of 2θ diffraction angles between 47° and 52°, at least two diffraction lines are present at diffraction angles 2θ of 48.3±0.2°, and 50.0±0.2°, the most intense diffraction lines being the one at 2θ of 50.0±0.2°, the intensity of the other diffraction line being equal to or lower than the intensity of the most intense diffraction line.
摘要:
Solid adducts comprising MgCl2 and water and optionally an organic hydroxy compound (A) selected from hydrocarbon structures containing at least one hydroxy group, said compounds being present in molar ratio defined by the following formula MgCl2.(H20)n(A)p in which n is from 0.6 to 6, p ranges from 0 to 3, said adduct having a porosity (PF), measured by the mercury method and due to pores with radius equal to or lower than 1 μm, of at least 0.15 cm3/g with the proviso that when p is 0, (PF) is equal to or higher than 0.3 cm3/g.
摘要:
Adducts comprising a MgCl2, an alcohol ROH in which R is a Cl—ClO hydrocarbon group, present in a molar ratio with MgCl2 ranging from 0.5 to 5 and less than 15% wt, based on the total weight of the adduct, of a metal salt of an aliphatic carboxylic acid having from 8 to 22 carbon atoms.
摘要:
The present invention relates to catalysts component for the polymerization of ethylene and its mixtures with olefins CH2═CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising Ti, Mg, halogen, and electron donor belonging to 1,2-diethers as internal electron donor compound. The catalyst of the invention is suitably used in (co)polymerization processes of ethylene to prepare (co)polymers having narrow Molecular Weight Distribution (MWD) and high bulk density.
摘要:
Adducts comprising a MgCl2, an alcohol ROH in which R is a C1-C10 hydrocarbon group, present in a molar ratio with MgCl2 ranging from 0.5 to 5 and less than 15% wt, based on the total weight of the adduct, of a metal salt of an aliphatic carboxylic acid having from 8 to 22 carbon atoms.
摘要:
Process for the preparation of solid particles of a magnesium-chloride alcohol adduct comprising (a) forming an emulsion between a MgCl2 alcohol adduct in molten form and a liquid phase which is immiscible with the said adduct in the presence of a polyalkyl-methacrylate used as a solution having viscosity ranging from 100 to 5000 mm2/s and (b) rapidly cooling the emulsion to solidify the disperse phase and collecting the solid adduct particles.
摘要:
A process for the preparation of propylene polymer compositions carried out in the presence of a catalyst system comprising (a) a solid catalyst component having average particle size ranging from 15 to 80 μm comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and at least two electron donor compounds one of which being present in an amount from 50 to 90% by mol with respect to the total amount of donors and selected from succinates and the other being selected from 1,3 diethers, (b) an aluminum alkyl and optionally (c) an external electron donor compound, and comprising the following steps: (i) contacting the catalyst components (a), (b) and optionally (c); (ii) pre-polymerizing up to forming amounts of polymer from about 0.1 up to about 1000 g per gram of solid catalyst component (a); (iii) polymerizing propylene producing a propylene (co)polymer being for at least 85% by weight of insoluble in xylene at 25° C. and (iv) in a successive step, carried out in gas-phase, polymerizing mixtures of ethylene with α-olefins CH2═CHR in which R is a hydrocarbon radical having 1-10 carbon atoms, to produce the said ethylene copolymer.
摘要:
A process for the preparation of propylene polymer compositions comprising from 50 to 90% by weight of a propylene polymer fraction insoluble in xylene at 25° C., and from 10 to 50% by weight of an ethylene copolymer fraction soluble in xylene at 25° C., said process being carried out in the presence of a specific catalyst system, is also characterized by the following step:(i) contacting the catalyst components (a), (b) and optionally (c) for a period of time ranging from 0.1 to 120 minutes, at a temperature ranging from 0 to 90° C.;(ii) polymerizing propylene in the optional presence of ethylene and/or C4-C10 alpha olefins producing a propylene (co)polymer being for at least 85% by weight of insoluble in xylene at 25° C. and(iii) in a successive step, carried out in gas-phase, in the presence of the product coming from (ii), polymerizing mixtures of ethylene with a-olefins CH2═CHR in which R is a hydrocarbon radical having 1-10 carbon atoms, to produce an ethylene copolymer. An increased reactivity in the last step is observed.
摘要:
A solid adduct comprising magnesium chloride and ethanol in which the moles of ethanol per mole of magnesium chloride range from 2 to 5 and in which the ratio between the average pore radius measured in Angstrom of said adduct, determined by mercury porosity, and the moles of ethanol, is higher than 500.