Poly(phenylene oxide) was incorporated by small amounts (1, 3, and 5 wt%) of hybrid macromolecular stars with fullerene C-60 core and polymer arms of different nature (six nonpolar arms polystyrene and six polar arms of diblock copolymer poly(2-vinyl pyridine)-b-poly(tert-butylmethacrylate). The properties of composite materials were studied in solutions (dynamic light scattering, capillary viscometry) and in the solid phase (TGA, X-ray diffraction analysis, and dielectric spectroscopy). To characterize physical properties, density and contact angles were determined. Transport properties were studied by measuring the permeability of H-2, O-2, N-2, and CH4 through films containing 0, 1, 3 and 5 wt% hybrid macromolecular stars. An increase of the modifier content in the composite leads to a certain decrease in the permeability coefficients for all gases, but the ideal selectivity in the separation of the O-2/N-2 and H-2/CH4 gas pairs increases.