This work reports the synthesis and characterization of a new polystyrene-based graft copolymer. By immobilization of transition metal complexes it shows high potential for selective heterogeneous hydrogenation under outstanding mild conditions. Here, a branched poly(ethylene imine) with average M(r) around 3 x 10(4) was used to be grafted on acetylated polystyrene beads. C-13 solid state NMR investigations demonstrate a high mobility and flexibility of the chains of this spacer due to branching as compared to, e.g., linear poly(ethylene glycol) with M(r) around 3000.