A series of polyamides containing aromatic or heteroaromatic and aliphatic fragments in their repeat unit were synthesized and used as supports to immobilize a catalyst based on a [RhCl(CO)(2)](2) precursor. The polymeric materials were characterized by differential scanning spectroscopy (DSC), wide-angle X-ray scattering (WAXS), small-angle X-ray scattering (SAXS), specific surface area and porosity measurements. The catalytic properties of polyamide-supported Rh(I) catalysts were studied in hydrosilylation of vinyl-type olefins. The selectivity of this reaction towards formation of the linear adducts over the branched ones was found to be greatly influenced by the matrix supramolecular structure when compared with that in the homogeneous phase. Based on SAXS measurements, the high selectivity of the polymer-immobilized rhodium catalysts was attributed to the matrix microporous structure displaying a narrow distribution of pores mostly in the range from r = 1.0 to 3.0 nm.