Study of polyurethane surface coatings based on (rosinified phenolic resincastor oil) blends with diisocyanates

Surface coating formulations were prepared by blending of rosinified phenolic resin with castor oil of different % weight ratio was carried out. Such obtained polyols were treated stoichiometrically hexamethylene diisocyanate (HMDI) and diphenylmethane diisocyanate (MDI) to afford polyurethane syrups. FT-IR analyses were monitoring for these polyurethane. These produce polyurethane syrups (i.e. resins) resins were casted into film. The result of polyurethane film were characterized for surface drying time, tack-free time,mechanical properties like scratch, impact, pencil hardness, adhesion and flexibility. The chemical properties like acid, alkalies and solvent resistance of these coats have also been checked.