HYDROGENATION OF LIQUID CARBOXYLATED NITRILE RUBBER

Hydrogenation of liquid carboxylated nitrile rubber (L-XNBR) was carri ed out using homogeneous palladium and rhodium catalysts. It was obser ved that the six-membered cyclic palladate complex of 2-benzoylpyridin e, 1, reduces the carbon-carbon double bonds without affecting the nit rile and carboxyl functionality. The intrinsic viscosity of the polyme rs remains unchanged during hydrogenation. The glass transition temper ature is marginally lowered for the hydrogenated products. A great ext ent of decarboxylation was obtained for samples hydrogenated in presen ce of the rhodium complex, 2.