Desenvolvimento de um pré-polímero de uretana a base de óleo de mamona e tolueno diisocianato (TDI)

Abstract

Polyurethanes are a very versatile class of polymeric materials, widely used in industry, and covering most diverse segments of applications. Main raw materials for polyurethanes are polyols and isocyanates. Polyols are generally derived from petroleum, a nonrenewable resource, so several alternative routes for the production of polyols have been studied. One of these is the obtaining of polyols from vegetable oils. Among the vegetables, castor oil stands out due to its low production costs, high productivity and the fact of being derived from a renewable resource. Crude castor oil is a hydroxylated natural compound, which can react directly with isocyanates to form urethane polymers. Obtaining urethane products from prepolymers is an interesting processing route in terms of control of the reaction and the toxicity of the reactants. In this paper was developed a pre-urethane polymer from a direct reaction of raw castor oil and TDI. The pre-polymer was characterized in terms of NCO content, viscosity and infra-red spectrometry. The material processability by casting was satisfactory, likewise castable elastomers polyurethane available on market. The final product, before the curing of the pre-polymer with glycol ethylene, has shown elastomers characteristics and good mechanical properties, compatible with application in technical parts, coating and adhesives.