Synthesis, characterization, and performance characteristics of alkyd resins based on Ricinodendron heudelotii oil and their blending with epoxy resins

Ricinodendron heudelotii oil is a good source of polyunsaturated fatty acid, mainly α-eleostearic, a triple conjugated double bonds diene fatty acid chain. Three sets of long oil alkyd resins based on R. heudelotii oil have been synthesized by a two stage alcoholysis-polyesterification process at relatively low temperatures (190 °C) with different molar ratio of phthalic and maleic anhydride. The synthesized alkyd resins were characterized by FT-IR, 1H-NMR, and 13C-NMR spectroscopy and gel permeation chromatography (GPC). The synthesized alkyd resins were blended with epoxy resin and methyl-ethyl ketone peroxide (MEKP) as initiator, cobalt-octoate as accelerator and poly(amido amine) as hardener. The blends were cured at room temperature and also at 50 °C. The cured resins exhibited improved performance characteristics in term of drying time at room temperature, adhesion and pencil hardness, gloss, and chemical resistance. The cured resins exhibited good tensile strength, improved elongation at break and thermally stable up to 400 °C.