Patent ID: 8536277
Filing Date: 2013-09-17
Classification: B01J

Abstract:
1. A process for reducing the molecular weight of nitrile rubber, comprising bringing into contact and reacting a nitrile rubber with a catalyst system, characterized in that the catalyst system comprises a metathesis complex catalyst and at least one compound of the general formula (Z): where BF D is water, diethyl ether, ethylamine, THF, n-propanol, formic acid, acetic acid, trifluoroacetic acid, trichloroacetic acid, sulphuric acid, phosphoric acid, trifluoromethanesulphonic acid or toluenesulphonic acid, and m is 1, 2, or 3, n is 0, 1, or 2, m+n=3, v is 1, 2, or 3, and wherein as the catalyst either compounds of the general formula (A), where M is osmium or ruthenium, X L represents identical or different ligands, the radicals R are identical or different and are each hydrogen, an alkyl, cycloalkyl, alkenyl, alkynyl, aryl, carboxylate, alkoxy, alkenyloxy, alkynyloxy, aryloxy, alkoxycarbonyl, alkylamino, alkylthio, arylthio, alkylsulphonyl, or alkylsulphinyl, where these radicals can all optionally be substituted by one or more alkyl, halogen, alkoxy, aryl- or heteroaryl radicals or alternatively the two radicals R are bridged with inclusion of the common C atom to which they are bound to form a cyclic group which can be aliphatic or aromatic in nature, are optionally be substituted and optionally contain one or more heteroatoms, or compounds of the general formula (B), where M is ruthenium or osmium, Y is oxygen (O), sulphur (S), an N—R X R R R L is a ligand which has the same meaning as the ligand L in formula (A), or compounds of general formula (C), where M is ruthenium or osmium, X the radicals R′ are identical or different and are organic radicals, Im is a substituted or unsubstituted imidazolidine radical and An is an anion, or compounds of general formula (D), where M is ruthenium or osmium, R X L L Y n is 0, 1, 2, 3, 4 or 5, or compounds of general formula (E), where M R R or compounds of general formula (F), where M is ruthenium or osmium, X L represents identical or different ligands which have the same meaning as L in the general formulae (A) and (B) and R or compounds of general formula (G), (H) or (K), or a catalyst (N) which has the general structural element (N1), where the carbon atom denoted by “*” is bound via one or more double bonds to the basic catalyst framework of a ruthenium- or osmium-carbene complex catalyst of the general formula (N10a) or (N10b): where M is ruthenium or osmium, X L n is 0, 1, 2, or 3, n′ is 1 or 2, and R m is 0 or; and A is oxygen, sulphur, C(R are used.