Corn. epoxy resin was modified by addn. of nanosized montmorillonite (1%) and an elastomeric oligourethane resin (5-15%), compounding a oligooxypropylene tricarbamate (soft segments) with a polyurethane made by condensation of PhOH sulfonic acid and urea with CH2O (hard segments), cured with triethylenetetraamine hardener to the epoxy-polyurethane nanocomposite studied then for impact and bending strength, stress intensity index, structure (IR spectra) and morphol. (scanning electron microscopy). The addn. of polyurethane resulted in an improvement of the nanocomposite properties.