摘要:
A modified Ziegler-Natta catalyst system, a method for preparing the catalyst system, and a process for polymerizing an olefin in the presence of the catalyst system are disclosed. The catalyst system comprises a titanium compound, an aluminum compound, and a nitroso compound. Improved polyolefin properties, such as high molecular weight, are obtained.
摘要:
A modified Ziegler-Natta catalyst system, a method for preparing the catalyst system, and a process for polymerizing an olefin in the presence of the catalyst system are disclosed. The catalyst system comprises a titanium or vanadium compound, an aluminum compound, and a 2-hydroxypyridine N-oxide. Improved properties such as increased molecular weight are obtained.
摘要:
Catalyst components for the polymerization of olefins comprising Mg, Ti, halogen and 1,3-diethers as internal donors having an improved balance of properties in terms of activity and morphological stability are obtained by a 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, with a titanium compound having at least a Ti—Cl bond at a reaction temperature ranging from 0° C. to 80° C.; (B) A subsequent step comprising contacting the solid product obtained in (A) with an electron donor ED selected from 1,3 diethers with a titanium compound having at least a Ti—Cl bond at a temperature higher than 80° C.; and (C) A subsequent step comprising reacting the solid product coming from (B) with a titanium compound having at least a Ti—Cl bond at a temperature higher than 80° C.
摘要:
Butene-1 (co)polymers characterized by the following properties: content of butene-1 units in the form of isotactic pentads (mmmm) from 25 to 55%; intrinsic viscosity [η] measured in tetraline at 135° C. from 1 to 3 dL/g; content of xylene insoluble fraction at 0° C. from 3 to 60%; and a ratio ES2/ES1≧1, where ES1 is the boiling diethyl ether soluble fraction determined on the polymer as such and ES2 is the boiling diethyl ether soluble fraction determined after milling the polymer. The butene-1 (co)polymers show a good balance between processability and elastomeric behavior.
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:
Propylene-ethylene copolymers are flexible and show a very good balance between softness and mechanical properties in their crude state are obtained by solution polymerization in the presence of Ziegler-Natta catalysts. The said copolymers comprise from 10 to 50% wt of ethylene and are characterized by: product of the comonomer reactivity ratio r1·r2≦1.5; absence of 2,1 propylene insertions and tensile strength at break higher than 4 Mpa.
摘要:
Catalysts components for the polymerization of ethylene comprising Ti, Mg, halogen, ORI groups, where RI is a C1-C12 hydrocarbon group optionally containing heteroatoms, having specific relationship among ORI/Ti and Mg/Ti molar ratio and characterized by a specific SS-NMR pattern are particularly useful for preparing narrow MWD crystalline ethylene polymers.
摘要:
A catalyst component for olefin (co)polymerization, and in particular for the preparation of LLDPE, comprising Mg, Ti, halogen and an electron donor compound (ED) belonging to ethers, esters, amines, ketones, or nitriles, characterized in that the molar ratio Mg/Ti is higher than 5, and the molar ratio ED/Ti is higher than 3.5. The said catalyst components display a homogeneous distribution of the comonomer in and among the copolymer chains.
摘要:
The present invention relates to a solid catalyst component for the polymerization of olefins CH2═CHR in which R is hydrogen or a hydrocarbon radical with 1-12 carbon atoms, comprising Mg, Ti, halogen and an electron donor selected from thiophene dicarboxylate derivatives of a particular formula. Said catalyst components when used in the polymerization of olefins, and in particular of propylene, are capable to give polymers in high yields and with high isotactic index expressed in terms of high xylene insolubility.
摘要:
Lewis base adducts comprising MgCln(OR)2-n, and an aprotic Lewis base that are in molar ratios to each other defined by the formula MgCln(OR)2-nLBp in which n is from 0.1 to 1.9, p is higher than 0.4, and R is a C1-C15 hydrocarbon group. The adducts of the present invention are particularly useful as precursors of Ziegler-Natta catalyst components for the polymerization of olefins.
摘要翻译:包含MgCl 3(OR)2-n N的路易斯碱加成物和彼此以摩尔比计的摩尔比为非离子路易斯碱,由式MgCl n 其中n为0.1至1.9,p高于0.4,R为C1-C15烃基。 本发明的加合物特别可用作烯烃聚合的齐格勒 - 纳塔催化剂组分的前体。