The properties of the rubbery matrix and the organization of the filler were analyzed in two elastomeric systems, viz. a high vinyl polybutadiene (HVBR) and a styrene butadiene random copolymer (SBR). the properties of the matrices were investigated using low resolution solid state NMR spectroscopy which give information mainly on the molecular motions in the elastomeric component, while the organization of the filler was analyzed using scanning electron microscopy (SEM). The results show differences in the molecular mobility phenomena in the two matrices, well correlable with differences observed in the mechanical behaviour.