The Impact of Film Properties on Corrosion Resistance in Waterborne Acrylics and Next Generation Low VOC Resin Development

摘要

Corrosion protection of organic coatings has received a significant amount of study in both academia and industry. Without considering anticorrosive pigments or other corrosion inhibiting additives, three of the most commonly highlighted factors influencing corrosion resistance are barrier properties (water and O_2 permeability), adhesion, and electrochemical impedance. When attempting to identify the rate limiting or primary protection mechanism, the various literature studies often conflict. Discrepancies may arise for a number of reasons including differences in polymer chemistries, test methods, and conditions. To explore the disagreements, a focused study of 21 styrenated-acrylic resins in clear formulations was conducted in an effort to correlate film properties with corrosion resistance on flat, bare, cold rolled steel. The study was then extended into high gloss pigmented systems. The structure property relationships derived from this work were then applied to the development of next generation, low volatile organic content (VOC), direct-to-metal polymers.