Synthesis of toluene disocyanate urethane prepolymer using castor oil and evaluation of mechanical properties

Abstract

This research is the synthesis of urethane prepolymer cast elastomer which had been produced using toluene diisocyanate and castor oil to replace the synthetic polyol, from petroleum origin, and the evaluation of mechanical properties of the polyurethane. The focus was to replace polyol from petroleum to vegetable material looking for renewable resources. The reactions occurred in a pilot reactor considering the process temperature of 70 degrees C and 0.5 bar of pressure. After the reactions, all prepolymers reacted with the chain extender to cast in sheet molds for mechanical properties. The chains extenders chosen to react with the prepolymers were 4,4'-methylenebis(2-chloroaniline) and castor oil. The better results achieved 65 Shore A as hardness, 35% as rebound resilience, 36.22 mm(3) as abrasion resistance, 570.12 psi as tensile strength, 325.39% as elongation and 29.53 kN m(-1) as tear resistance; achieved using a blend between castor oil and polytetramethylene ether glycol with 2000 g mol(-1) as molecular weight. Thought the mechanical results tests, the castor oil can replace the synthetic polyol depending on applications which did not require a high tensile strength and tear resistance, such as rolls for graphics and cellulose processes, billets seals, cushions and general parts used for industrial segment.