Abstract:
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 1,2- dimethoxyethane 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.
Abstract:
A terpolymer containing propylene, ethylene and 1-hexene obtainable by the step of copolymerizing propylene, ethylene and 1-hexene in the presence of a catalyst system comprising the product obtained by contacting the following components: (a) a solid catalyst component 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 40 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 hydrocarbyl compound, and (c) optionally an external electron donor compound. wherein in the terpolymer (i) the content of 1-hexene derived units ranges from 0.5 to 5.0 wt%; (ii) the content of ethylene derived units is higher than 1.4 t% and fulfils the following relation (1): C �¢ 2
Abstract:
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.
Abstract:
The present invention relates to a slurry process for preparing an ethylene polymer having a melt flow ratio F/P, which is the ratio among the melt index value measured according to ASTM 1238 condition "F" and the melt index value measured according to ASTM 1238 condition "P" of equal to or lower than 27, carried out in two or more stages of polymerization at temperatures in the range from 60 to 120°C, in which at least two of the said two or more polymerization stages are carried out under different amounts of molecular weight regulator, said process being carried out in the presence of (A) a solid catalyst component comprising Ti, Mg, halogen, having a porosity (P F ), measured by the mercury method and due to pores with radius equal to, or lower than, 1µm, of at least 0.3 cm 3 /g and a surface area determined by BET method, of lower than 100 m 2 /g, and being further characterized by the fact that more than 50% of the titanium atoms are in a valence state lower than 4 and (B) of an organoaluminum compound.
Abstract:
Process for the preparation of a porous propylene carried out in the presence of a catalyst system comprising (a) a Ziegler-Natta catalyst containing 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 comprising the following steps: i) contacting the catalyst components (a) and (b) for a period of time ranging from 1 to 60 minutes, at a temperature ranging from 35 to 55°C; optionally, ii) pre-polymerizing with one or more olefins of formula CH2=CHR, where R is H or a C1-C10 hydrocarbon group, up to forming amounts of polymer from about 0.1 up to about 1000 g per gram of solid catalyst component (a); and iii) polymerizing propylene in the optional presence of minor amounts of ethylene and/or C4-C10 alpha olefins producing said porous propylene (co)polymer.
Abstract:
Propylene terpolymers are prepared by polymerizing propylene, ethylene and an alpha-olefin selected from the group of C4-C8 alpha-olefins in the presence of a catalyst system obtained by contacting a solid catalyst component 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 40 to 90% by mol with respect to the total amount of donors and selected from succinates and the other selected from 1,3 diethers, an aluminum hydrocarbyl compound, and optionally an external electron donor compound.