METAL PALLADIUM SUPPORTED ON AMPHIPHILIC MICROPOROUS SYNTHETIC ORGANIC SUPPORTS - PART II - CATALYTIC INVESTIGATIONS

Two sets of resin-supported Pd(0) catalysts were compared in the hydro genation of cyclohexene in methanol, under ambient conditions. Two lig htly crosslinked poly-{styrene/2-methacryloxyethylsulfonic acid/methyl enebisacrylamide} with different degrees of crosslinking (1 and 3 mol% ), have been used as catalyst supports. Two catalysts with different p alladium loadings (0.22 and 2.2 wt%) have been prepared from each supp ort. When the size of the particles was relatively small, the catalyst s with 2.2% and 0.22% Pd were almost equally active with respect to th e amount of palladium in the reaction mixture. In contrast, when large r catalyst particles were used, catalysts with 2.2% metal produced con version profiles typical of diffusion-controlled regimes (productivity decreased with increasing crosslinking). These catalysts were charact erised by combined ESR and static gradient spin echo NMR spectrometrie s, which have provided information about molecular motion inside the p olymer networks. (C) 1998 Elsevier Science B.V.