A study of the erosive wear damage on a recycled polymer coating

Abstract

In this work, erosion tests were carried out to study the wear damage on a coating made of a recycled polymeric matrix (crystal polystyrene) and clay (montmorillonite (MMT)). The latter was modified and purified with bromide quaternary salts (hexadecyltrimethyl ammonium bromide). The coating preparation was by liquid via dissolving 25% crystal polystyrene in a solution of 70% ethyl acetate and 30% acetone, after this, 1wt% of modified MMT clay was added. The clay/polystyrene matrix coating was applied by immersing wood substrates in the liquid phase of the mixture. This process was repeated five times to get the final coating layer on the substrates. An erosion rig similar to that in ASTM G76-95 was used to perform the tests. The abrasive particle used to conduct the erosion tests was glass beads with a particle size between 200 and 240µm. The impact angles were 30°, 45°, 60° and 90° with a velocity of 2.5±0.5m/s. The abrasive flow rate was 5.5±0.5g/min. The room temperature was between 35°C and 40°C. The results showed that the coating presented its maximum erosion rate at 45°. In addition, the erosion rates were decreased in the clay–polystyrene coating compared to those observed in the uncoated specimens at all incident angles. The wear mechanisms identified in SEM images were consistent pitting action, radial cracks and deposition of particle fragments on the coating surfaces.