Abstract:
A porous solid adduct comprising magnesium chloride and ethanol characterized by a specific relation between content of alcohol, average pore radius and amount of porosity deriving from pores with radius comprised between 100 and 1000 nm is provided to generate catalyst components which in turn generate polyolefins endowed with higher porosity.
Abstract:
A processfor the preparation of propylene polymer compositions comprising from 50 to 90 % by weight of a propylene (co)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 comprising: (i)a first step of polymerizing propylene in the optional presence of ethylene and/or C 4 - C 10 alpha olefins, to produce a propylene (co)polymer being for at least 85% by weight insoluble in xylene at 25°C; and (ii)a successive step, carried out in gas-phase, in the presence of the product coming from step (i), of copolymerizing a mixture of ethylene with one or more α-olefins CH 2 =CHR in which R is a hydrocarbon radical having 1-10 carbon atoms, to produce an ethylene copolymer; the process being carried out in the presence of a catalyst system comprising: the product obtained by contacting: (a) a solid catalyst component comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and at least two internal electron donor compounds one of which being present in an amount from 35 to 90% by mol with respect to the total amount of donors and being selected from succinates and the other being selected from 1,3-diethers, the total amount of internal electron donor compounds being lower than 14.0% by weight with respect to the total weight of the solid catalyst component; with (b) an aluminum hydrocarbyl compound, and optionally with (c) an external electron donor compound.
Abstract:
Catalyst components for the polymerization of olefins comprising Mg, Ti, halogen and 1,3- diethers as internal donors having an improved balance of properties in terms of activity and morphological stability are obtained by a process comprising: (A) A first step comprising reacting an adduct of formula MgC1 2 (ROH) n , where R is a C1-C10 alkyl group, and n is from 0.5 to 6, with a titanium compound having at least a Ti-C1 bond at a reaction temperature ranging from 0°C to 80°C; (B) A subsequent step comprising contacting the solid product obtained in (A) with an electron donor ED selected from 1,3 diethers with a titanium compound having at least a Ti-C1 bond at a temperature higher than 80°C; and (C) A subsequent step comprising reacting the solid product coming from (B) with a titanium compound having at least a Ti-C1 bond at a temperature higher than 80°C.
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 CH 2 =CHR, where R is H or a C 1 -C 10 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 C 4 -C 10 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.
Abstract:
Prepolymerized catalyst component for the polymerization of olefins CH 2 =CHR, wherein R is hydrogen or a C 1 -C 12 hydrocarbyl group, comprising a solid catalyst component characterized by comprising Mg, Ti halogen and an electron donor (ID) selected from the alkyl esters of aromatic dicarboxylic acids in such an amount that the molar ratio ID/Mg ranges from 0.025 to 0.07 and the Mg/Ti molar ratio is higher than 13, said prepolymerized catalyst component containing an amount of ethylene pre-polymer up to 5Og per g of said solid catalyst component.
Abstract:
A process for the preparation of random copolymer of propylene containing up to 6.0 % by weight of ethylene units, suitable for the manufacture of pipes, by copolymerizing propylene and ethylene 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) n aluminum hydrocarbyl compound, and (c) optionally an external electron donor compound.
Abstract:
Fibers comprising a polypropylene obtainable by a process comprising the steps of: (i) polymerizing propylene 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, to obtain a polypropylene precursor having a melt flow rate MFRl; (ii) subjecting the thus-obtained polypropylene precursor to visbreaking to obtain a visbroken polypropylene having a melt flow rate MFR2; (iii) spinning the visbroken polypropylene obtained in the previous step; wherein MFR2 is comprised between from 15 to 40 g/10min, the ratio MFR2/MFR1 is comprised between 8 and 18, both MFRl and MFR2 being measured according to ISO method 1133 (230° C, 2.16 kg).
Abstract:
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.
Abstract:
Catalyst component for the polymerization of olefins comprising Mg, Ti, halogen and an electron donor is obtained by a batch process comprising: (A) A first step comprising reacting an adduct of formula MgCl 2 (ROH) n , where R is a C1-C10 alkyl group, and n is from 0.5 to 6, in a liquid medium comprising a titanium compound having at least a Ti-Cl bond at a temperature ranging from 0°C to 80°C and then removing the liquid medium; (B) A subsequent step comprising reacting the solid product obtained in (A) in a liquid medium comprising an electron donor ED selected from ethers, esters, ketones, silanes, amines, nitriles and amides, and a titanium compound having at least a Ti-Cl bond at a temperature higher than 80°C and then, after removing the liquid medium; (C) A subsequent step comprising reacting the solid product coming from (B) with a liquid medium comprising a titanium compound having at least a Ti-Cl bond at a temperature higher than 80°C.