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 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 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.

1) Hydrocarbon copolymer P comprising 2 alkoxysilane end groups F.sup.1 and F.sup.2 of formulae: F.sup.1: (RO).sub.3-tR.sub.tSi(CH.sub.2).sub.g1- and F.sup.2: (CH.sub.2).sub.d1SiR.sub.t(OR).sub.3-t; or F.sup.1: (RO).sub.3-tR.sub.tSiRO(O)C(CH.sub.2).sub.g2 and F.sup.2: (CH.sub.2).sub.d2C(O)ORSiR.sub.t(OR).sub.3-t; wherein t is 0, 1 or 2; g1 and d1 are 1, 2 or 3; g2 and d2 are 0, 1, 2 or 3; R et R represent a C.sub.1-C.sub.4 alkyl; R is a C.sub.1-C.sub.4 alkylene radical; the main chain comprising motifs (I) and (II) in which R.sup.0 is in particular the methyl radical; and the number average molecular mass Mn thereof being between 400 and 100,000 g/mol. 2) Method for producing said copolymer, comprising: (i) a step of heating a statistical bipolymer A selected from a poly(butadiene-isoprene), a poly(butadiene-myrcene) and a poly(butadiene-farnesene); and subsequently (ii) a step of heating the formed product, in the presence of a chain transfer agent of formula (C). 3) Adhesive composition comprising said copolymer.

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.

This invention relates to novel catalyst compositions based on Ruthenium- or Osmium-based complex catalysts of the Grubbs-Hoveyda, Grela or Zhan type and specific co-catalysts comprising at least one vinyl group, pref. ethyl vinyl ether, and to a process for selectively hydrogenating nitrile rubbers in the presence of such catalyst compositions, preferably with a preceding metathesis step using the same complex catalyst as in the hydrogenation step.

This invention relates to novel catalyst compositions based on Ruthenium- or Osmium-based complex catalysts of the Grubbs-Hoveyda, Grela or Zhan type and specific co-catalysts comprising at least one vinyl group, pref. ethyl vinyl ether, and to a process for selectively hydrogenating nitrile rubbers in the presence of such catalyst compositions, preferably with a preceding metathesis step using the same complex catalyst as in the hydrogenation step.