摘要:
This invention relates to novel homopolymers important for applications where a high density is needed to ensure certain mechanical properties like abrasion resistance, indentation resistance, pressure resistance, topload resistance, modulus of elasticity, or morphology (for the chlorination of PE to CPE) and additional advantages such as melt processability. This invention also relates to blend compositions containing the novel homopolymer, the use of which allows the incorporation of more comonomer in the additional components of the blend (for the same overall density) resulting in increased tie molecule formation and improvement in properties such as ESCR, toughness and impact strength. The blend can be obtained by dry or melt mixing the already produced components, or through in-situ production by in parallel and/or in series arranged reactors. These resins can be used in applications such as films, blow molded, injection molded, and rotomolded articles, fibres, and cable and wire coatings and jacketings and, various forms of pipe.
摘要:
A process for the preparation of blends comprising an ethylene copolymer, which is prepared by polymerizing ethylene and at least one comonomer selected from (a) a compound represented by the formula H2C═CHR, wherein R is an alkyl group, an aryl group, or (b) a diene. The polymerization takes place in the presence of a solid catalyst system comprising a support, a transition metal compound and an activator capable of converting the transition metal compound into a catalytically active transition metal complex.
摘要:
A supported polymerisation catalyst system comprises a porous support, a polymerisation catalyst and a cocatalyst wherein the support has been treated with an inert material such as polyisobutene. The support is preferably silica and is preferably treated with the inert material prior to contact with the other components. Preferably the polymerisation catalyst is a metallocene and the polymerisation catalyst system reduces the initial peak isotherm allowing for a smoother activity increase in particular for polymerisations carried out in the gas phase.
摘要:
A transition metal complex having the following Formula (A): wherein the monovalent groups R1 and R2 are —Ra, —ORb, —NRcRd, and —NHRe: the monovalent groups Ra, Rb, Rc, Rd and Re, and the divalent group R3 are (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v); M is a Group (3) to (11) or lanthanide metal; E is phosphorus or arsenic; X is an anionic group, L is a neutral donor group; n is (1) or (2), y and z are independently zero or integers, such that the number of X and L groups satisfy the valency and oxidation state of the metal M. n is preferably (2) and the two resulting R1 groups are preferably linked. The complex can be used with optional activator to polymerise olefins.
摘要:
A transition metal complex having the following Formula (A): wherein the monovalent groups R1 and R2 are —Ra, —ORb, —NRcRd, and —NHRe: the monovalent groups Ra, Rb, Rc, Rd and Re, and the divalent group R3 are (i) aliphatic hydrocarbon, (ii) alicyclic hydrocarbon, (iii) aromatic hydrocarbon, (iv) alkyl substituted aromatic hydrocarbon (v) heterocyclic groups and (vi) heterosubstituted derivatives of said groups (i) to (v); M is a Group (3) to (11) or lanthanide metal; E is phosphorus or arsenic; X is an anionic group, L is a neutral donor group; n is (1) or (2), y and z are independently zero or integers, such that the number of X and L groups satisfy the valency and oxidation state of the metal M. n is preferably (2) and the two resulting R1 groups are preferably linked. The complex can be used with optional activator to polymerise olefins.
摘要:
A method for the preparation of a supported transition metal catalyst system which includes the steps of: (i) mixing together in a suitable solvent (a) an aluminoxane and (b) an ionic activator containing a cation and an anion, wherein the anion has at least one substituent containing a moiety having an active hydrogen, (ii) addition of the mixture from step (i) to a support material, and (iii) addition of a transition metal compound in a suitable solvent. The use of tetraisobutylaluminoxane as the aluminoxane results in a more stable activity profile and improved polymer properties in particular melt strength.
摘要:
Supported catalyst systems are provided comprising (a) a transition metal compound, (b) an activator comprising (iii) an aluminoxane or (iv) a Group IIIA metal or metalloid compound, and (c) a support material comprising an inorganic metal oxide, inorganic metal halide or polymeric material or mixtures thereof characterised in that the support material has been pretreated with a source of a transition metal atom. The preferred transition metal compounds are metallocenes and the source of the transition metal atom is typically a ferrous or cupric metal salt. The supported catalyst systems show improved activity and also may reduce fouling in gas phase fluidised bed processes.
摘要:
An improved method for the preparation of a supported polymerisation catalyst system comprises the combination of (i) a porous support (ii) a polymerisable monomer, (iii) a polymerisation catalyst, and (iv) a cocatalyst, characterised in that the polymerisable monomer is added to the porous support before addition of one or both of the polymerisation catalyst and the cocatalyst. The preferred polymerisation catalyst is a metallocene complex and the preferred porous support is silica. The resultant supported catalysts are stable over long periods of time. The supported catalyst are particularly suitable for use in the gas phase.
摘要:
A novel process for the preparation of a supported transition metal catalyst system said method comprises the steps of: (i) mixing together in a suitable solvent (a) an organometallic compound, and (b) an ionic activator comprising a cation and an anion, (ii) addition of the mixture from step (i) to a support material, and (iii) addition of a transition metal compound in a suitable solvent, characterised in that the molar ratio of organometallic compound (a) to ionic activator (b) in step (i) is in the range 0.1 to 2.0. By use of the reduced molar ratio of the organometallic compound to the ionic activator in step (i) better reproducibilty of the catalyst may be achieved as well as higher activities. In addition polymer properties may be improved for example higher melt strength resulting in better product performance. The preferred transition metal compounds are metallocenes.
摘要:
A cocatalyst or cocatalyst component, including a compound corresponding to the formula: (A*+a)b(Z*J*j)−cd, wherein: A* is a cation of from 1 to 80 atoms, not counting hydrogen atoms, Z* is an anion group of from 1 to 50 atoms, not counting hydrogen atoms, containing two or more Lewis base sites; J* is a Lewis acid of from 1 to 80, not counting hydrogen atoms, coordinated to at least one Lewis base site, and optionally two or more such J* groups may be joined together in a moiety having multiple Lewis acidic functionality, j is from 2 to 12 and a, b, c, and d are integers from 1 to 3, with the proviso that a×b is equal to c×d, and provided further that one or more of A*, Z* or J* comprises a hydroxyl group or a polar group containing quiescent reactive functionality.