摘要:
Solid Lewis adducts comprising MgCl2, a Lewis base (LB) belonging to ethers, esters, ketones, silanes or amines and an alcohol ROH, in which R is a C1-C15 hydrocarbon group optionally substituted with heteroatoms containing groups, which compounds are in molar ratios to each other defined by the following formula MgCl2(ROH)m(LB)n in which m ranges from 0.05 to 6, n ranges from 0.08 to 6. The solid Lewis adducts herein can be used to prepare catalysts having good morphological stability, and high polymerization activity.
摘要:
A catalyst component for the polymerization of olefins comprising a titanium compound, a Mg-dihalide, a difunctional electron donor compound (ED) selected from diesters, diketones, diamines or diethers, and a monofunctional electron donor compound (MD) selected from ethers, esters, amines or ketones, wherein a molar ratio ED/MD is higher than 10.
摘要:
Catalyst component for the polymerization of olefins obtainable by contacting: (i) a magnesium halide, or a suitable precursor; (ii) a monofunctional electron donor compound (MD) selected from ethers, esters, amines or ketones, used in such amounts to have Mg/MD molar ratios of at least 50; (iii) a titanium compound of formula Ti(ORI)n-yXy, where n is the valence of titanium, y is a number between 1 and n, X is halogen, and RI is a C1-C15 hydrocarbon group and, optionally, (iv) an electron donor compound (ED). The said catalyst component shows improved activity in the polymerization of olefins.
摘要:
A catalyst component for the polymerization of olefins comprising a titanium compound, a Mg-dihalide, a difunctional electron donor compound (ED) selected from diesters, diketones, diamines or diethers, and a monofunctional electron donor compound (MD) selected from ethers, esters, amines or ketones, wherein a molar ratio ED/MD is higher than 10.
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:
An olefin polymer composition comprising (by weight, unless otherwise specified): A) 60-85% of a crystalline propylene homopolymer or a crystalline copolymer of propylene containing 3% or less of ethylene or C4-C10 α-olefin(s) or of combinations thereof, said homopolymer or copolymer having a Polydispersity Index (P.I.) value of from 4.5-6 and a content of isotactic pentads (mmmm), measured by 13C NMR on the fraction insoluble in xylene at 25° C., higher than 96%; B) 15-40% of a partially amorphous copolymer of ethylene containing from 35% to 70% of propylene or C4-C10 α-olefin(s) or of combinations thereof, and optionally minor proportions of a diene. The said olefin polymer composition exhibits a value of elongation at break ranging from 150 to 600% according to ISO method 527.
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.