Abstract:
A borohydride metallocene complex of a lanthanide, its process of preparation, a catalytic system incorporating a borohydride metallocene complex and a process for the copolymerization of olefins employing this catalytic system. Such a complex corresponds to one or other of the following formulae A and B: where, in the formula A, two ligands Cp1 and Cp2, each composed of a cyclopentadienyl group, are connected to the lanthanide Ln, such as Nd, and where, in the formula B, a ligand molecule, composed of two cyclopentadienyl groups Cp1 and Cp2 which are connected to one another via a bridge P of formula MR1R2, where M is an element from group IVa, such as Si, and where R1 and R2, which are identical or different, represent an alkyl group comprising from 1 to 20 carbon atoms, is connected to the lanthanide Ln, where L represents an alkali metal, such as Li, where N represents a molecule of a complexing solvent, such as THF, where x is an integral or non-integral number greater than 0, where p is an integer equal to or greater than 1 and where y is an integer which is equal to or greater than 0.
Abstract:
The present invention relates to a process for preparing an activating support for metallocene complexes in the polymerisation of olefins comprising the steps of: I) providing a support prepared consisting in particles formed from at least one porous mineral oxide; II) optionally fixing the rate of silanols on the surface of the support; III) functionalising the support with a solution containing a fluorinated functionalising agent; IV) heating the functionalised and fluorinated support of step c) under an inert gas and then under oxygen; V) retrieving an active fluorinated support. That activating support is used to activate a metallocene catalyst component for the polymerisation of olefins.
Abstract:
Disclosed are ethylene and butadiene copolymers and a catalytic system usable for the synthesis of these copolymers. The copolymers have a molar content of units resulting from butadiene of ≧8%, said units comprising trans-1,2 cyclohexane linkages, and a number-average molecular mass Mn of ≧40,000 g/mol. The catalytic system includes: (i) an organometallic complex represented by one of the following formulae A or B: where Ln represents a lanthanide and X a halogen, where, in the formula A, two ligand molecules Cp1 and Cp2 each consisting of a fluorenyl group, are attached to Ln, where, in the formula B, a ligand molecule consisting of two fluorenyl groups Cp1 and Cp2, joined together by a bridge P of formula MR2, where M is an element of column IVa and R is an alkyl with 1 to 20 carbon atoms, is attached to Ln, and (ii) a co-catalyst selected from an alkylmagnesium, an alkyllithium, an alkylaluminium, a Grignard reagent, or a mixture of these constituents. The (co-catalyst/organometallic complex) molar ratio falls within a range of from 1 to 8.
Abstract:
A catalytic system usable for the copolymerization of at least one conjugated diene and at least one monoolefin, a process for preparing this catalytic system, a process for preparing a copolymer of a conjugated diene and at least one monoolefin using said catalytic system, and said copolymer are described. This catalytic system includes: (i) an organometallic complex represented by the following formula: {[P(Cp)(Fl)Ln(X)(Lx)}p (1) where Ln represents a lanthanide atom to which is attached a ligand molecule comprising cyclopentadienyl Cp and fluorenyl Fl groups linked to one another by a bridge P of the formula MR1R2, M is an element from column IVa of Mendeleev's periodic table and R1 and R2 each represent alkyl groups of 1 to 20 carbon atoms or cycloalkyl or phenyl groups of 6 to 20 carbon atoms, X represents a halogen atom, L represents an optional complexing molecule, such as an ether, and optionally a substantially less complexing molecule, such as toluene, p is a natural integer greater than or equal to 1 and x is greater than or equal to 0, and (ii) a co-catalyst selected from alkylmagnesiums, alkyllithiums, alkylaluminums, Grignard reagents and mixtures of these constituents.
Abstract:
The present invention relates to a multi-component catalytic system that can be used for the cis-1,4 stereospecific polymerization of conjugated dienes. The system is based on: (i) a rare-earth complex of Formula (II) Ln(A)3(B)n, Ln being a rare-earth metal, A a ligand, B a Lewis base or a solvent molecule and n a number from 0 to 3; (ii) an alkylating agent; (iii) a compound based on an aromatic ring and having at least two heteroatoms chosen from the elements O, N, S, P, and corresponding to the Formula (III): in which the R groups each denote hydrogen, an alkyl radical optionally comprising one or more heteroatoms (N, O, P, S, Si) or one or more halogen atoms, a halogen atom, a group based on one or more heteroatoms (N, O, P, S, Si); x and y are integers from 0 to 6; D is a group having a chemical function, one of the atoms of which has a non-bonding pair; L being an atom from column 1 of the Periodic Table.
Abstract:
Activating supports may be suitably prepared by the following procedure (a) providing a porous mineral oxide support material, (b) treating the support with a phosphorus-containing compound, (c) treating the support from step (b) with an organometallic compound, (d) heating the functionalized support from step (c) under an inert gas and then under an atmosphere comprising oxygen, (e) fluorinating the support with a fluorinating agent, and (f) recovering an activating support. The activating supports are suitable used in combination with single site catalysts for the polymerization of olefins. The supports are most preferably used in combination with metallocene complexes. The preparative route for the activating supports provides for supported polymerization catalyst systems having excellent activities.
Abstract:
Borohydride metallocene complex of lanthanide, preparation process, catalytic system incorporating it, copolymerization of olefins employing catalytic system and ethylene/butadiene copolymer, the butadiene units comprise 1,2-cyclohexane or 1,2- and 1,4-cyclohexane links. The complex corresponds to of formulae A and/or B: where, in A two ligands Cp1 and Cp2, each of a fluorenyl group, are connected to the lanthanide Ln, where, in B, a ligand molecule, composed of two fluorenyl groups Cp1 and Cp2 are connected via bridge P of formula MR1R2, is an element from group IVa, R1 and R2, which are identical or different, represent an alkyl group comprising from 1 to 20 carbon atoms, connected to lanthanide Ln, L is alkali metal, N is molecule of a complexing solvent, x is integral or non-integral number ≧0 and p is integer ≧1.
Abstract:
A borohydride metallocene complex of a lanthanide, its process of preparation, a catalytic system incorporating it, a process for the copolymerization of olefins employing this catalytic system and an ethylene/butadiene copolymer obtained by this process, the butadiene units of which comprise 1,2-cyclohexane or 1,2- and 1,4-cyclohexane links. This complex corresponds to one or other of the following formulae A and B: where, in the formula A, two ligand molecules Cp1 and Cp2, each composed of a fluorenyl group, are connected to the lanthanide Ln, such as Nd, and where, in the formula B, a ligand molecule, composed of two fluorenyl groups Cp1 and Cp2 which are connected to one another via a bridge P of formula MR1R2, where M is an element from group IVa, such as Si, and where R1 and R2, which are identical or different, represent an alkyl group comprising from 1 to 20 carbon atoms, is connected to the lanthanide Ln, where L represents an alkali metal, such as Li, where N represents a molecule of a complexing solvent, such as THF, where x is an integral or non-integral number greater than 0 and where p is an integer equal to or greater than 1.
Abstract:
A borohydride metallocene complex of a lanthanide, its process of preparation, a catalytic system incorporating a borohydride metallocene complex and a process for the copolymerization of olefins employing this catalytic system. Such a complex corresponds to one or other of the following formulae A and B: where, in the formula A, two ligands Cp1 and Cp2, each composed of a cyclopentadienyl group, are connected to the lanthanide Ln, such as Nd, and where, in the formula B, a ligand molecule, composed of two cyclopentadienyl groups Cp1 and Cp2 which are connected to one another via a bridge P of formula MR1R2, where M is an element from group IVa, such as Si, and where R1 and R2, which are identical or different, represent an alkyl group comprising from 1 to 20 carbon atoms, is connected to the lanthanide Ln, where L represents an alkali metal, such as Li, where N represents a molecule of a complexing solvent, such as THF, where x is an integral or non-integral number greater than 0, where p is an integer equal to or greater than 1 and where y is an integer which is equal to or greater than 0.