P-cresol/Formaldehyde-Based Sunflower Epoxy Esters for Surface Coatings

Abstract

Epoxy esters were prepared by reacting sunflower oil fatty acids with epoxy resins which were prepared by the epoxidation of P-cresol/formaldehyde resins (1:1, 3:2, 2:1). The epoxy esters were blended with alkyd resin and the film characteristics of these blends were studied at different pigmentation level. It was found that the cured films showed excellent resistance to water and solvents (acetone, ethanol, methanol, ethylmethylketone, toluene), while the resistance to alkali (10% NaOH) was poor. It was also found that increasing the ratio of P-cresol/formaldehyde increase the acid resistance and no significant difference was observed with these tests. All the coating films exhibited a very good adhesion to metallic substrate, good impact, scratch hardness, and flexibility.

Keywords:

• Chemical resistance
• epoxy ester
• formaldehyde epichlorohydrin
• P-cresol
• mechanical resistance

Notes

∗p-cresol/formaldehyde (1:1, 3:2, 2:1) epoxy sunflower esters.

Pbw = parts by weight.