Synthesis, characterization of poly(urethane amide) resins from Nahar seed oil for surface coating applications

Poly(urethane amide) resins with varying ratio of NCO/OH (0.8:1-2:1) have been synthesized for the first time from purified Nahar oil (Mesua ferrea) with toluene diisocyanate (TDI) in the presence of dibutyl tin dilaurate (DBTDL) as the catalyst. The poly(urethane amide) resins have been synthesized from N,N-bis(2-hydroxy ethyl) M. ferrea fatty amide, obtained from methyl esters of the oil by treatment with diethanolamine. Again, the methyl esters of the oil were obtained by the treatment of purified Nahar oil with super dry methanol in the presence of sodium methoxide (NaOMe) as the catalyst. The synthesized intermediates and resins have been characterized by FT-IR and H-1 NMR spectroscopic analysis and by measurement of physico-chemical properties like acid value, iodine value, saponification value, hydroxy value, drying time, viscosity, etc. The coating performance of the resins was tested by measurement of gloss, pencil hardness, impact resistance, adhesion and chemical resistance. The results show better performance of the poly(urethane amide) resins compared to polyester or polyesteramide resins of the same oil. Thus, this study shows that these resins hold promise for use as effective surface coating materials. (c) 2005 Elsevier B.V. All rights reserved.