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:
Films or sheets of polypropylene, particularly biaxially oriented polypropylene (BOPP) films, exhibiting excellent physical and mechanical properties combined with good processing characteristics can be prepared from propylene polymers prepared in the presence of Ziegler-Natta catalysts comprising a succinate and a diether compound.
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:
Films or sheets of polypropylene, particularly biaxially oriented polypropylene (BOPP) films, exhibiting excellent physical and mechanical properties combined with good processing characteristics can be prepared from propylene polymers prepared in the presence of Ziegler-Natta catalysts comprising a succinate and a diether compound.
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 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 a-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:
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:
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.