Synthesis of high-performance alkyd anticorrosion coatings based on waste poly(ethylene terephthalate)

Abstract

Synthesis of high-performance anticorrosive coatings obtained from alkyd resins (ARs) based on waste poly(ethylene terephthalate) (PET) glycolyzates is presented. PET glycolyzates, synthesized by catalytic depolymerization with trimethylolpropane (TMP) and dipropylene glycol (DPG), were used as replacement of part of the polyhydroxylic component during the ARs synthesis. The obtained glycolyzates and ARs were analyzed using FT-IR and 1HNMR spectroscopy and acid, iodine, and hydroxyl value were determined. Thickness, adhesion, swelling, corrosion, spraying and layering of the synthesized ARs, as well as alkyd coating film were determined in accordance with SRPS EN ISO standards. ARs were produced in high yields and FT-IR and 1NMR analysis results confirmed assumed structures. All synthesized ARs show good elasticity, flexibility, adhesion and the gloss values are greater than 85 %, and the alkyd coating films based on AR1 and AR3 showed best corrosion results. The most effective dryer catalyst combination was 0.5 wt.% Ca, 0.03 wt.%, Co and 0.45 wt.% Zr.