Abstract:
A propylene 1-hexene copolymer containing from 5.5 to 9.0% by weight, of 1-hexene derived units having: a) two peaks in the DSC plot having a difference in height ranging from 0 to 5 mW; b) the higher melting temperature, measured by DSC, ranging from 141.0 °C to 151.0 °C; c) Melt Flow Rate (MFR, measured according to ASTM D 1238, 230°C/2.16 kg, from 3.5 to 8.0 g/10 min.
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 MFR1; (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 MFR1 and MFR2 being measured according to ISO method 1133 (230° C, 2.16 kg).
Abstract:
Polyolefin compositions particularly suitable for cast film, exhibiting heat sealability, retortability, low haze and stiffness, comprising: 1) 75-85% of a propylene homopolymer or copolymer of propylene with ethylene and/or one or more C 4 -C 10 α-olefin(s), the homopolymer or copolymer having melting temperature equal to or higher than 150°C, 2) 15-25% of a copolymer of ethylene with one or more C 4 -C 10 α-olefin(s) containing from 20 to 30% of said C 4 -C 10 α-olefin(s); said composition having MFR (at 230°C, 2.16 kg) of from 5-10 g/10 min, the total content of ethylene of from 10 to 20 %, the total content of C 4 -C 10 α-olefin(s) of from 2 to 8 %, the ratio XStot/XSm of the total fraction soluble in Xylene at room temperature to the fraction soluble in Xylene at room temperature of the matrix component (1) of from 5 to 15, and the value of the intrinsic viscosity of the total fraction soluble in Xylene at room temperature (XSIVtot) of 1.5 dl/g or less.
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:
A masterbatch composition comprising: 70-90 %wt of a component (A) being a propylene homopolymer or copolymer of propylene with ethylene or C 4 -C 10 alpha olefins, having a MFR A according to ISO 1133 (230°C/2.16 Kg) ranging from 15 to 70 g/10 min; and 10-30 %wt of a component B) being a propylene-ethylene copolymer comprising 25-45 %wt of ethylene derived units and having a value of the intrinsic viscosity [η] of the fraction soluble in xylene at room temperature ranging from 5 to 9 dl/g, said masterbatch composition having a total MFR higher than 4 g/10 min, and a value of the fiexural modulus measured according to ISO method 178 ranging from 950 to 2000 MPa.
Abstract:
Random propylene/ethylene copolymers are provided characterized by Ethylene content in the range of 4.5-7%wt; Mw/Mn (via GPC) in the range 3.5-5.5; Mz/Mw (via GPC) lower than 4; absence of 2-1 regioinversion, and Melting Temperature (Tm) (non-nucleated grade) lower than 143°C. The said copolymers show an excellent balance of impact and optical properties which is retained even after visbreaking.
Abstract:
Random propylene/ethylene copolymers are provided characterized by Ethylene content in the range of 4.5-7%wt; Mw/Mn (via GPC) in the range 3.5-5.5; Mz/Mw (via GPC) lower than 4; absence of 2-1 regioinversion, and Melting Temperature (Tm) (non-nucleated grade) lower than 143°C. The said copolymers show an excellent balance of impact and optical properties which is retained even after visbreaking.
Abstract:
A process for the preparation of polyolefins comprising the step of polymerizing an olefin in the liquid phase in the presence of a polymerization catalyst and of an antistatic composition, wherein the polymer slurry is conveyed in a transfer line comprising a horizontal section and a series of vertical sections connected by bent sections, with the antistatic composition injected in the first portion of the first section of the series of vertical sections.