Synthesis of polyurethane using soybean oil based polyol and characterization of their coating properties

Polymeric coatings based on renewable sources such as soybean oil is very attractive due to its low cost and biodegradable properties. The modification of two different polyols from soybean oil had been done in lab scale for polyurethane (PU) synthesis application. By reacting the modified polyol with Isophorone diisocyanate (IPDI) adduct, where different ratios of NCO/OH were used, polyurethane of various composition had been obtained. The samples of polyols and polyurethane obtained were characterized by FTIR spectroscopy. Types of Polyols prepared with various ratio of NCO/OH in each type of modification had been studied for coating properties (hardness, tensile and adhesion strength onto wood substrate). The result showed that the hardness and tensile strength of polyurethane is dependent on the ratio of NCO/OH.