Polyurethane adhesive system from castor oil modified by a transesterification reaction

This study reports the preparation of polyurethane adhesives using polyols obtained from castor oil modified by a transesterification reaction with pentaerythritol. The physical properties of the polyols such as hydroxyl value have been determined and the infrared (IR) spectroscopic analysis of the polyols is reported. The polyols were reacted with aliphatic isocyanate (isophorone diisocyanate) to form polyurethane coatings (NCO/OH ratio = 1). The effect of varied pentaerythritol content in the polyols on the physical properties of polyurethane coatings on wood and steel panels was determined. The characterization of polyurethane coatings carried out by IR spectroscopic analysis and the physicomechanical properties such as hardness, adhesion properties, solvent resistance and chemical resistant determination were reported.