摘要:
Process for the preparation of ethylene polymers having narrow MWD characterized by a F/E ratio lower than 35 carried out in the presence of a catalyst system comprising (a) a solid catalyst component comprising Ti atoms that are substantially in the +4 oxidation state, Mg, Cl, and optionally OR groups and internal donors in which R is a C1-C20 hydrocarbon group, in which the OR/Ti molar ratio is equal to or lower than 0.35 and the internal donor/Ti ratio is lower than 1, (b) an aluminum alkyl compound and (c) a compound selected from alkoxybenzenes of specified formula.
摘要:
A pre-polymerized catalyst component for the polymerization of olefins CH2═CHR, wherein R is hydrogen or a C1-C12 hydrocarbon group, characterized by comprising a non-stereospecific solid catalyst component, comprising Ti, Mg and a halogen, said pre-polymerized catalyst component containing an amount of a (co)polymer of a monomer having formula CH2═CHA, where A is a C6 aliphatic or aromatic ring, optionally substituted, up to 5 g per g of said solid catalyst component. Said prepolymerized catalyst shows an excellent balance in terms of activity, morphological stability, reduced tendency to agglomeration and hydrogen response.
摘要:
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.
摘要:
Catalyst components for the polymerization of olefins CH2=CHR wherein R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms, comprising Mg, Ti, Cl and a diol or a derivative thereof. A process for the use of catalyst components for the polymerization of olefins CH2=CHR wherein R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms, comprising Mg, Ti, Cl and a diol or a derivative thereof.
摘要:
A solid catalyst component for olefin polymerization, and in particular for the preparation of LLDPE, comprising Mg, Ti, halogen and an electron donor compound (ID) belonging to cyclic ethers having 3-6 carbon atoms, characterized by having the molar ratio Mg/Ti higher than 5, the molar ratio Mg/ID lower than 3, and by a specific X-ray diffraction spectrum.
摘要:
A catalyst component comprising Ti, Mg, Al, Cl, and optionally OR1 groups in which R1 is a C1-C20 hydrocarbon group, optionally containing heteroatoms, up to an amount such as to give a molar OR1/Ti ratio lower than 0.5, characterized by the fact that substantially all the titanium atoms are in valence state of 4, that the porosity (PF), measured by the mercury method and due to pores with radius equal to or lower than 1 μm, is at least 0.3 cm3/g, and by the fact that the Cl/Ti molar ratio is lower than 29.The said catalysts are characterized by high morphological stability under the low molecular weight ethylene polymerization conditions while at the same time maintaining characteristics of high activity.
摘要:
Solid adducts comprising a MgCl2, ethanol and a compound (A), said compounds being present in molar ratios defined by the following formula MgCl2.(EtOH)n(A)p in which n is from 0.1 to 6, p ranges from 0.001 to 0.5 and A is a compound selected from cyclic hydrocarbon structures which are substituted with at least two hydroxy groups.
摘要:
A process for the (co)polymerization of propylene carried out at a temperature ranging from 77 to 95° C. in the presence of a catalyst comprising the product obtained by reacting: —an organo-aluminium compound, with—-a solid catalyst component comprising Mg, Ti and electron donor compound selected from specific diolesters.
摘要:
A process for the preparation of high purity propylene polymers carried out in the presence of a catalyst comprising the product obtained by reacting:—an organo-aluminium compound, with—a solid catalyst component comprising Mg, Ti and electron donor compound selected from specific diolesters, said process being carried out employing an organo-aluminum/propylene ratio equal to or lower than 1.75 mmole/kg.
摘要:
Disclosed is a method for making LLDPE grades having different xylene solubles or hexane extractables with the same Ziegler-Natta catalyst by varying the amount of alkylaluminum used for polymerization. The method comprises copolymerizing ethylene with a C3-10 α-olefin in the presence of a Ziegler-Natta catalyst, an alkylaluminum, and an electron donor; determining the dependency of the xylene solubles or hexane extractables on the alkylaluminum/electron donor ratio; and adjusting the alkylaluminum/electron donor ratio to achieve a desired xylene solubles or hexane extractables.