Abstract:
A bridged metallocene compound of formula (I) wherein: M is an atom of a transition metal; X, is a hydrogen atom, a halogen atom, or a hydrocarbon-based group; R1 is a C1-C40 hydrocarbon radical; R2 and R3, form together a condensed 3-7 membered ring; R4 is a hydrogen atom or a C1-C40 hydrocarbon radical; W is an aromatic 5 or 6 membered ring.
Abstract:
The present invention relates to catalysts for the polymerization of ethylene and its mixtures with olefins CH2═CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising (A) a solid catalyst component comprising Ti, Mg, halogen, and optionally an electron donor compound in a donor/Ti molar ratio lower than 3, (B) an aluminum alkyl compound and (C) a silicon compound of formula RmSi(OEt)n in which R is C1-C20 alkyl group, m is an integer ranging from 1 to 3, n is (4-m) with the proviso that when R is equal to, or higher than, C3 m is 1 or 2. The catalyst of the invention is suitably used in (co)polymerization processes of ethylene to prepare (co)polymers having narrow Molecular Weight Distribution (MWD) and high activity.
Abstract:
Catalyst component for the polymerization of olefins comprising Mg, Ti, halogen and an electron donor is obtained by a batch process comprising: (A) A first step comprising reacting an adduct of formula MgCl2(ROH)n, where R is a C1-C10 alkyl group, and n is from 0.5 to 6, in a liquid medium comprising a titanium compound having at least a Ti—Cl bond at a temperature ranging from 0° C. to 80° C. and then removing the liquid medium; (B) A subsequent step comprising reacting the solid product obtained in (A) in a liquid medium comprising an electron donor ED selected from ethers, esters, ketones, silanes, amines, nitriles and amides, and a titanium compound having at least a Ti—Cl bond at a temperature higher than 80° C. and then, after removing the liquid medium; (C) A subsequent step comprising reacting the solid product coming from (B) with a liquid medium comprising a titanium compound having at least a Ti—Cl bond at a temperature higher than 80° C.
Abstract:
The present invention relates to catalysts for the polymerization of olefins, in particular ethylene and its mixtures with olefins CH2═CHR, wherein R is an alkyl, cycloalkyl or aryl radical having 1-12 carbon atoms, comprising a solid catalyst component comprising Ti, Mg, halogen and optionally an electron donor, an aluminum alkyl compound and a particular class of silanes compounds as external electron donor compounds. The catalysts of the invention are suitably used in (co)polymerization processes of ethylene to prepare (copolymers having narrow Molecular Weight Distribution (MWD) and high activity.
Abstract:
Propylene polymers having a content of isotactic pentads (mmmm) higher than 97%, molecular weight distribution, expressed by the formula (a) ratio, equal to or higher than 6 and a value of formula (b) ratio equal to or lower than 5.5. The said polymers are prepared in the presence of a particular combination of Ziegler-Natta solid catalyst components and highly stereoregulating electron-donor compounds. Laminated articles, in particular bi-axially oriented films and sheets, can be prepared with the said polymers. M _ w / M _ n ( a ) M _ z / M _ w ( b )
Abstract translation:具有高于97%的全同立构五单元组(mmmm)含量的丙烯聚合物,由式(a)比率表示的分子量分布等于或高于6,式(b)的值等于或低于5.5 。 所述聚合物在齐格勒 - 纳塔固体催化剂组分和高度立构调节电子给体化合物的特定组合的存在下制备。 可以用所述聚合物制备层压制品,特别是双轴取向膜和片材。 M _ w / M _ n(a)M _ z / M _ w(b)
Abstract:
Soft polyolefin composition with improved processability comprising from 8 to 45% by weight of a polypropylene component (A), from 82 to 45% by weight of an elastomeric component (B), and from 10 to 25% by weight of a viscosity reducing agent (C) comprising polybutene-1 and paraffinic wax or grease. The composition is easily processable also by injection moulding and has better tensile properties than compositions in which processability is improved by visbreaking.
Abstract:
Use of propylene polymers having Polydispersity Index value P.I.(2) greater than or equal to 15 for the nucleation of polypropylene resins having a Polydispersity Index value P.I.(1) fulfilling the equation P.I.(2)−P.I.(1)≧10.
Abstract:
The present subject matter relates generally to polymer compositions, and more particularly to irradiated polymer compositions comprising at least one non-phenolic stabilizer. The present polymer compositions comprise an unexpected balance of properties after being subjected to irradiation treatments, including an unexpected combination of a lower melt flow rate ratio (MFRr) and high melt tension after being irradiated, while minimizing negative yellowing effects.
Abstract:
A catalyst component comprising Ti, Mg, Cl, and optionally ORI groups in which RI is a C1-C20 hydrocarbon group up to an amount such as to give a molar ORI/Ti ratio lower than 0.5, characterized by the following properties: surface area, determined by BET method, of lower than 80 m2/g, a total porosity (PT), measured by the mercury method, in the range of 0.60-1.50 cm3/g a difference (PT−PF) of higher than 0.1 in which PT is the total porosity and PF is the porosity due to pore with radius equal to or less than 1 μm; an amount of Ti in the catalyst component of less that 10% wt based on the total weight of catalyst component. The said catalyst components show high morphological stability under the low molecular weight ethylene polymerization conditions while at the same time maintaining characteristics of high activity.
Abstract:
The instant invention relates to a process for preparing a catalyst component for the polymerization of olefins. Catalysts prepared with this catalyst component provide a high mileage for the production of polyolefin with a high bulk density of the polymer produced therewith. Particularly, catalysts prepared with this catalyst component are suitable for the improved economical production of polyolefin in gas phase processes.