HYDROGENATION OF DIENE-BASED POLYMER LATEX IN THE PRESENCE OF AN IN SITU SYNTHESIZED CATALYST

摘要

A technique of improving the hydrogenation reaction of diene-based polymers, present in aqueous suspension, by in-situ synthesizing the catalyst in the presence of a specific aliphatic alcohol is disclosed. The process allows the selective hydrogenation of the carbon-carbon double bonds in the diene-based polymers with a high degree of hydrogenation and short reactions times. The improved process eliminates the complicated catalyst synthesis operations so far necessary.

主权项

1. A process for selectively hydrogenating carbon-carbon double bonds in a diene-based polymer, the process comprising subjecting the diene-based polymer which is present in an aqueous suspension to a hydrogenation by contacting the diene-based polymer with a catalytically active system characterized in that
(i) the catalytically active system is based on a first main catalyst component having either the general formula (Ia)
MQx.a H2O  (Ia)whereinN is a group VIII transition noble metal,Q is identical or different, and a hydride or an anion other than a hydride,x is 1, 2, or 3, anda is in the range of from 0 to 3,  or having the general formula (Ib)
RhQ′Ly   (Ib)whereinQ′ is a hydride or an anion other than a hydride,y is 1, 2, 3 or 4, andL is identical or different and a water-soluble ligand  and on a secondary water-insoluble catalyst component having either the general formula (IIa) or the general formula (IIb)
R1mD  (IIa)(R2)2E-A-E(R2)2  (IIb)  in which
R1 is identical or different and represents hydrogen, alkyl,D is phosphorus, nitrogen, arsenic, sulfur, or a sulphoxide group S═O, andm is 2 or 3,R2 is identical or different and represents hydrogen, alkyl,E is phosphorus, phosphorus, or arsenic,A represents either a single bond or a divalent spacer group  and (ii) the catalytically active system is prepared in-situ in the presence of an aliphatic C1 to C5 alcohol.