The invention relates to a diorganomagnesium compound of formula R.sup.B—Mg—R.sup.A, R.sup.B being different from R.sup.A, R.sup.B comprising a benzene nucleus substituted with a magnesium atom, one of the carbon atoms of the benzene nucleus ortho to the magnesium being substituted with a methyl, an ethyl, an isopropyl or forming a ring with the carbon atom which is its closest neighbour and which is meta to the magnesium, the other carbon atom of the benzene nucleus ortho to the magnesium being substituted with a methyl, an ethyl or an isopropyl, R.sup.A being an alkyl, a cycloalkyl or a benzyl, which may be substituted or unsubstituted, which diorganomagnesium compound is other than n-butylmesitylmagnesium. When used as co-catalyst of a metallocene, it makes it possible to increase the functional group content in the synthesis of a functional polymer.

The invention relates to a diorganomagnesium compound of formula R.sup.B—Mg—R.sup.A, R.sup.B being different from R.sup.A, R.sup.B comprising a benzene nucleus substituted with a magnesium atom, one of the carbon atoms of the benzene nucleus ortho to the magnesium being substituted with a methyl, an ethyl, an isopropyl or forming a ring with the carbon atom which is its closest neighbour and which is meta to the magnesium, the other carbon atom of the benzene nucleus ortho to the magnesium being substituted with a methyl, an ethyl or an isopropyl, R.sup.A being an alkyl, a cycloalkyl or a benzyl, which may be substituted or unsubstituted, which diorganomagnesium compound is other than n-butylmesitylmagnesium. When used as co-catalyst of a metallocene, it makes it possible to increase the functional group content in the synthesis of a functional polymer.

The present invention provides an organometal catalyst having a cationic metal complex and a borate-based bulky anion, where the metal is one or more selected from the group consisting of metals in group 13, a method for preparing the same, and a method for preparing an oligomer or a polymer using the same.

The present invention provides an organometal catalyst having a cationic metal complex and a borate-based bulky anion, where the metal is one or more selected from the group consisting of metals in group 13, a method for preparing the same, and a method for preparing an oligomer or a polymer using the same.

In a process for producing an olefin polymer, at least one olefin monomer is polymerized in a polymerization reactor to produce a particulate polymer product containing hydrocarbon impurities including unreacted monomer and other C.sub.1 to C.sub.8 hydrocarbons. The polymer product is contacted with a gas-containing stream in a stripping vessel under conditions effective to strip hydrocarbon impurities from the polymer product and produce a stripped particulate polymer product and a gaseous first effluent stream containing inert gas and hydrocarbon impurities. The stripped particulate polymer product is recovered and the atmosphere adjacent the stripped particulate polymer product is sensed with a photoionization detector configured to ionize C.sub.4 to C.sub.8 hydrocarbons. The amount of the gas-containing stream supplied to the stripping vessel is then adjusted based upon such sensing.

In a process for producing an olefin polymer, at least one olefin monomer is polymerized in a polymerization reactor to produce a particulate polymer product containing hydrocarbon impurities including unreacted monomer and other C.sub.1 to C.sub.8 hydrocarbons. The polymer product is contacted with a gas-containing stream in a stripping vessel under conditions effective to strip hydrocarbon impurities from the polymer product and produce a stripped particulate polymer product and a gaseous first effluent stream containing inert gas and hydrocarbon impurities. The stripped particulate polymer product is recovered and the atmosphere adjacent the stripped particulate polymer product is sensed with a photoionization detector configured to ionize C.sub.4 to C.sub.8 hydrocarbons. The amount of the gas-containing stream supplied to the stripping vessel is then adjusted based upon such sensing.

A process for preparing a polydiene, the process comprising (i) forming an active catalyst composition by combining a rare-earth compound, an alkylating agent, an aluminoxane, and a halogen compound; and (ii) combining the active catalyst composition with monomer to be polymerized within 12 hours of forming the active catalyst composition.

A process for preparing a polydiene, the process comprising (i) forming an active catalyst composition by combining a rare-earth compound, an alkylating agent, an aluminoxane, and a halogen compound; and (ii) combining the active catalyst composition with monomer to be polymerized within 12 hours of forming the active catalyst composition.

Disclosed are catalyst systems comprising the reaction product of at least the following: A) a procatalyst; and B) at least one cocatalyst structure selected from the following i) through iii): i) at least one cocatalyst comprising an anion having Structure 1 as shown below: ##STR00001##  as described herein; or ii) at least one cocatalyst comprising an anion having Structure 2 as shown below: ##STR00002##  as described herein; or iii) a combination of i and ii.

Disclosed are catalyst systems comprising the reaction product of at least the following: A) a procatalyst; and B) at least one cocatalyst structure selected from the following i) through iii): i) at least one cocatalyst comprising an anion having Structure 1 as shown below: ##STR00001##  as described herein; or ii) at least one cocatalyst comprising an anion having Structure 2 as shown below: ##STR00002##  as described herein; or iii) a combination of i and ii.