Abstract:
A process for 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 C4-C10 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 CH2═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:
A polypropylene composition made from or containing: A) from 71 wt % to 91 wt % of a propylene homopolymer, B) from 5 wt % to 15 wt % of a copolymer of propylene and ethylene containing from 18 wt % to 32.0 wt % of ethylene derived units; and C) from 4 wt % to 15 wt % of a copolymer of propylene and ethylene containing from 75 wt % to 90.0 wt % of ethylene derived units.
Abstract:
A propylene 1-hexene copolymer containing from 5.7 to 7.7% by weight of 1-hexene derived units, based upon the total weight of the propylene 1-hexene copolymer, having: a) a solubility in xylene at 25° C. ranging from 7.0 wt % to 15.0 wt %, based upon the total weight of the propylene 1-hexene copolymer; b) a melting temperature, measured by DSC ranging from 143.0° C. to 148.0° C.; c) a Melt Flow Rate (MFR, measured according to ASTM D 1238, 230° C./2.16 kg) from 3.5 to 8.0 g/10 min.; and d) a content of 1-hexene derived units in the fraction soluble in xylene at 25° C. ranging from 13.5 wt % to 18.5 wt %, based upon the total weight of the soluble fraction.
Abstract:
A polyolefin composition made from or containing: A) from about 19 wt % to about 50 wt % of a propylene ethylene copolymer having an ethylene derived units content ranging from about 1.5 wt % to about 6.0 wt % B) from about 50 wt % to about 81 wt % of a propylene ethylene 1-butene terpolymer having an ethylene derived units content ranging from about 1.5 wt % to about 6.0 wt % and 1-butene derived units content between about 4.8 wt % and about 12.4 wt %; the sum of the amount of component A) and B) being 100; the polyolefin composition being characterized by the following features: molecular weight distribution (MWD), expressed in terms of Mw/Mn, greater than about 4.0; the creep and recovery curve measured on the polymer fuse at 200° C. shows a maximum value between 600 and 1200 seconds, lower than about 53×10−4 1/Pa.
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:
A process for the preparation of high purity propylene polymers carried out in the presence of a catalyst comprising the product obtained by contacting: (a) a solid catalyst component comprising Mg, Ti and at least a first internal electron donor compound (HD) selected among the succinates and a second internal electron donor compound (2ID) selected among the 1,3-diethers, wherein the molar ratio of first internal donor over second internal donor 1ID:2ID is comprised between 4:6 and 9:1, with (b) an organo-aluminium compound, and optionally with (c) an external electron donor compound, said process being carried out at a temperature equal or higher than 78° C. and by employing a molar ratio of organo-aluminum compound over solid catalyst component (b):(a) of lower than 5.