Two-component semi-interpenetrating polymer networks (Semi-IPNs) of thermoplastic urethane elastomer based on poly(ethylene glycol) and polymethyl methyacrylate were synthesized by the sequential technique. The Semi-IPNs obtained were characterized with respect to their mechanical properties such as tensile strength, elongation. Glass transition temperatures were carried out using dynamic mechanical thermal analysis. Phase morphology was studied by scanning electron microscopy. The effect of the compositional variation on the above-mentioned properties was examined. The results demonstrate that the components are immiscible, phase separation at the micrometer scale is observed, the extent of interpenetrating is dependent on variations in composition.