RHCL(PPH(3))(3) AND RHH(PPH(3))(4) CATALYZED HYDROGENATION OF ACRYLONITRILE-BUTADIENE COPOLYMERS

Homogeneous catalyst precursors of the forms RhCl(PPh(3))(3) and RhH(P Ph(3))(4) are applied commercially for the selective hydrogenation of acrylonitrile-butadiene copolymers. This report details a study of the ir catalytic behavior at reaction conditions approaching those found i n industrial settings. Detailed kinetic and selectivity data, collecte d according to a statistical design framework, have clearly defined th e effect of varying process conditions. The kinetic results suggest th e behavior observed under severe conditions is consistent with that re ported for pressures and temperatures near ambient. Dilute solution vi scosity data are used to demonstrate the uniform selectivity of both R hCl(PPh(3))(3) and RhH(PPh(3))(4) catalyzed hydrogenations. A probable reaction mechanism for the RhCl(PPh(3))(3) system has been derived us ing analysis of variance model discrimination procedures.