A catalytic membrane reactor, which was immobilized with palladium-loaded nanogel particles (NPs), was developed for continuous-flow Suzuki coupling reaction. Palladium-loaded membranes were prepared by immobilization of NPs, adsorption of palladium ions, and reduction into palladium(0). The presence of palladium in the membrane was confirmed by the scanning electron microscopy; palladium aggregation was not observed. The catalytic activity of the membrane reactor in continuous-flow Suzuki coupling reaction was approximately double that of a comparable reactor in which palladium ions were directly adsorbed onto an aminated membrane. This was attributed to the formation of small palladium particles. The reusability in the continuous-flow system was higher than that in a batch system, and the palladium-loaded membrane reactor had high long-term stability.

Palladium-loaded polymer nanoparticles with basic functional groups were prepared. When palladium ions were adsorbed on the polymer nanoparticles, the maximum loading capacity on the nanoparticles depended on the basic functional groups in the particles. The reduced palladium had a nanoscale average diameter. The palladium-loaded polymer nanoparticles exhibited catalytic activity for hydrogenation and Suzuki coupling reactions. The catalytic activity of the nanosized palladium-loaded nanoparticles was higher than that of bulk palladium.