摘要:
A propylene polymer composition comprising (percent by weight): A) 68%-80%, of a propylene homopolymer having a Polydispersity Index (P.I.) value of from 4.7 to 10 and MFR L (Melt Flow Rate according to ISO 1133, condition L, i.e. 230° C. and 2.16 kg load) from 10 to 30 g/10 min; B) 20%-32%, of a copolymer of propylene containing from 40.1% to 42.5% extremes included of ethylene derived units; the composition having an intrinsic viscosity of the fraction soluble in xylene at 25° C. comprised between 3 and 6 dl/g and a MFR L from 4 to 12 g/10 min Said Propylene polymer composition being particularly suitable for injection moulded articles having high rigidity and high impact properties at room and at low temperatures.
摘要:
The present invention provides polyolefin composition comprising a 50-80 wt % of propylene homopolymer or copolymer and a first and a second ethylene/alpha-olefin copolymer, said composition having good stress whitening resistance and gloss, in combination with a good balance of mechanical properties.
摘要:
Polyolefin compositions, comprising (percent by weight): 1) 55-80% of a homopolymer or copolymer of propylene, said copolymer containing up to 15% of ethylene and/or C4-C10 α-olefin(s). 2) 20-45% of a copolymer of ethylene with one or more C4-C10 α-olefin(s) containing from 10 to 40% of said C4-C10 α-olefin(s); said compositions having values of MFR (230° C., 2.16 kg) up to 20 g/10 min, a total content of ethylene of 20% or more, a total content of C4-C10 α-olefin(s) of 4.5% or more, a ratio of the total content of ethylene to the total content of C4-C10 α-olefin(s) of 2.3 or more, a total fraction soluble in xylene at room temperature of 18 wt % or higher and flexural modulus, referred to the composition as a reactor grade, of more than 700 MPa.
摘要:
A polypropylene composition comprising (percent by weight) (a) 50-77 % of a crystalline propylene polymer having an amount of isotactic pentads (mmmm), measured by 13C-MNR on the fraction insoluble in xylene at 25° C., higher than 97.5 molar % and a polydispersity index ranging from 4 to 10; (b) 13-28 % of an elastomeric copolymer of ethylene and propylene, the copolymer having an amount of recurring units deriving from ethylene ranging from 30 to 70 % and being partially soluble in xylene at ambient temperature, the polymer fraction soluble in xylene at ambient temperature having an intrinsic viscosity value ranging from 2 to 4 dl/g; and (c) 10-22 % of polyethylene having an intrinsic viscosity value ranging from 1 to 3 dl/g, in said composition component (b) plus component (c) being in amounts of at least 25 wt %. The polymer composition exhibits good impact resistant, whitening resistance and relatively low stiffness.
摘要:
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 C4-C10 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 C4-C10 α-olefin(s) containing from 20 to 30% of said C4-C10 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 C4-C10 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.
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 α-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 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 propylene polymer composition comprising (percent by weight): A) 74%-84% of a propylene homopolymer having a Polydispersity Index (P.I.) value of from 4.6 to 10, a fraction insoluble in xylene at 25° C., higher than 90%, and a MFR L (Melt Flow Rate according to ISO 1133, condition L, i.e. 230° C. and 2.16 kg load) from 110 to 200 g/10 min; B) 16%-26%, of a copolymer of propylene with from 39% to 48%, of ethylene derived units; the composition having an intrinsic viscosity of the fraction soluble in xylene at 25° C. comprised between 2.7 and 4.0 dl/g; and a MFR L (Melt Flow Rate according to ISO 1133, condition L, i.e. 230° C. and 2.16 kg load) from 30 to 80 g/10 min.
摘要:
A propylene polymer composition comprising (percent by weight): A) 74%-84% of a propylene homopolymer having a Polydispersity Index (P.I.) value of from 4.6 to 10, a fraction insoluble in xylene at 25° C., higher than 90%, and a MFR L (Melt Flow Rate according to ISO 1133, condition L, i.e. 230° C. and 2.16 kg load) from 110 to 200 g/10 min; B) 16%-26%, of a copolymer of propylene with from 39% to 48%, of ethylene derived units; the composition having an intrinsic viscosity of the fraction soluble in xylene at 25° C. comprised between 2.7 and 4.0 dl/g; and a MFR L (Melt Flow Rate according to ISO 1133, condition L, i.e. 230° C. and 2.16 kg load) from 30 to 80 g/10 min.
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.