The present invention relates to the synthesis of porous polymer scaffold from polyethyleneglycol-polyurethane having castor oil linkages under controlled conditions and their use as stem cell delivery vehicles thereby accelerating the tissue regeneration process. The present invention further studies the biodegradability, stability and biocompatibility of porous polymer scaffolds in various cell lines and primary bone marrow stem cells. Particularly the present invention further relates to the physio-chemical characterization of the porous polymer scaffolds.