UV weathering and performance of a novel corrosion protective coating on steel made from recycled polyethylene terephthalate (PET)
Mônica Martiniano Ferreira, Elisângela A. da Silva, Fernando Cotting, Vanessa de Freitas Cunha Lins
Abstract
Poly(ethylene terephthalate) (PET) powder obtained from post-consumer bottles is deposited on carbon steel by using a hot mechanical pressing method. The PET coated steels are aged in weathering chambers by using a xenon lamp for 400 and 1500 h, and using ultraviolet (UV-B) lamps for 400 h. The aged PET coatings are analysed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and the photodegradation mechanism is discussed. The corrosion evaluation of aged PET coated steels is performed by using the electrochemical impedance spectroscopy in a saline medium. FTIR-ATR analysis of the aged coating indicates that the UV-B test chamber is more aggressive to PET coatings than the WO chamber test. After 400 h of weathering aging, PET coated steels exposed in a chamber with the xenon radiation show a higher corrosion resistance than the PET coated steel aged using the UV-B test.