The present invention relates to a catalyst system containing a metathesis catalyst containing at least one N-heterocyclic carbene ligand and at least one phenolic compound and to a process for performing the metathesis on nitrile rubbers for reducing their molecular weight using a metathesis catalyst containing at least one N-heterocyclic carbene ligand (NHC ligand) and at least one phenolic compound.

The present invention relates to a catalyst system containing a metathesis catalyst containing at least one N-heterocyclic carbene ligand and at least one phenolic compound and to a process for performing the metathesis on nitrile rubbers for reducing their molecular weight using a metathesis catalyst containing at least one N-heterocyclic carbene ligand (NHC ligand) and at least one phenolic compound.

The present invention provides a novel process for subjecting a diene-based-polymer to a metathesis reaction in a first step and a selective hydrogenation of the carbon-carbon double bonds present in such diene-based polymers in a second step using a ruthenium or osmium based complex catalyst, wherein the diene-based polymer is present in latex form, this means as a suspension of diene-based polymer particles in an aqueous medium.

The present invention relates to the use of Ru and Os carbene complexes with a hydroxamic acid (ester) function for the metathesis degradation of nitrile rubber (NBR). The invention further relates to a method for producing hydrogenated nitrile rubbers, by subjecting a nitrile rubber to a metathesis degradation in the presence of the said catalyst, and the degraded nitrile rubber obtained subsequently undergoes a hydrogenation, preferably in situ.

The present invention relates to a catalyst composition containing: one or more selected from the group consisting of a transition metal compound represented by Formula 1 and a transition metal compound represented by Formula 3, and dialkyl L-tartrate; a cleaning liquid composition containing the catalyst composition; and a method of cleaning a polymerization apparatus using the cleaning liquid composition,

##STR00001## wherein all the variables are described herein.

The present invention relates to the use of specific catalysts for the metathesis degradation of nitrile rubber (NBR). The invention further relates to a method for preparing nitrile rubber with reduced molecular weight using specific catalysts.

This invention relates to novel hydrogenation catalyst compositions obtainable from reacting metal-based complex hydrogenation catalysts with specific co-catalysts and to a process for selectively hydrogenating nitrile rubbers in the presence of such novel hydrogenation catalyst compositions.

The present invention relates to a process for preparing nitrile rubbers having reduced molecular weight by metathesis of a first nitrile rubber in the presence of specific ruthenium complex catalysts that have particular N-heterocyclic carbene ligands.

1) Hydrocarbon-based copolymer comprising two end groups preceded by an ester function and chosen from a 2-oxo-1,3-dioxolan-4-yl (or cyclocarbonate), a dithiocyclocarbonate, an exo-vinylene cyclocarbonate and a 2-oxo-1,3-dioxolen-4-yl, the main chain of which comprises units (I) and (II) ##STR00001## in which R.sup.0 is notably a methyl radical; and the number-average molecular mass Mn of which is between 400 and 100 000 g/mol. 2) Process for preparing said copolymer, comprising: (i) a step of heating a statistical bipolymer A chosen from a poly(butadiene-isoprene), a poly(butadiene-myrcene) and a poly(butadiene-farnesene); and then (ii) a step of heating the product formed, in the presence of a chain-transfer agent. 3) Use as adhesive, as a mixture with an amine compound comprising at least two amine groups.

1) Hydrocarbon-based copolymer comprising two end groups preceded by an ether function and chosen from a 2-oxo-1,3-dioxolan-4-yl (or cyclocarbonate), a dithiocyclocarbonate, and a 2-oxo-1,3-dioxolen-4-yl, the main chain of which comprises units (I) and (II) ##STR00001## in which R.sup.0 is notably a methyl radical; and the number-average molecular mass Mn of which is between 400 and 100 000 g/mol. 2) Process for preparing said copolymer, comprising: (i) a step of heating a statistical bipolymer A chosen from a poly(butadiene-isoprene), a poly(butadiene-myrcene) and a poly(butadiene-farnesene); and then (ii) a step of heating the product formed, in the presence of a chain-transfer agent. 3) Use as adhesive, as a mixture with an amine compound comprising at least two amine groups.