Comparative Study on the Performance of Solvent-Based and Waterborne Polyurethane Top-Coats in Laboratory Accelerated Test and Field Test

Abstract

Taking solvent-based acrylic polyurethane top-coat and waterborne aliphatic polyurethane top-coat as the research objects， this study explored the effects of two laboratory accelerated aging methods (neutral salt spray， xenon lamp aging) and natural environmental exposure (Hainan Island) on the aging failure of the two top-coats under the condition of matching the primer and intermediate coat.The salt spray resistance of the coating was assessed by observing changes in the macro/micro morphology and gloss loss rate of top-coats.Electrochemical impedance spectroscopy and infrared absorption spectroscopy were utilized to compare and analyze the difference of anti-corrosion and anti-aging properties of the two coatings，both before and after undergoing xenon lamp aging and natural environmental aging tests.Results showed that under each accelerated failure test，the waterborne polyurethane coating was found to have better salt-spray resistance.Additionally，it was observed that the solvent-based acrylic polyurethane top-coat exhibited superior anti-corrosion properties and better aging resistance after the aging test.

Keywords

• polyurethane top-coat|neutral salt spray|aging test|anti-corrosion property