Film Properties and Formulation Considerations for Corrosion Resistance in Styrenated Acrylic Metal Coatings

The mechanisms by which organic coatings protect metal surfaces from corrosion have received a significant amount of study in both academia and industry, with significant disagreement over which is of primary importance.  Three of the most commonly highlighted film properties influencing corrosion resistance are barrier properties (water and O2 permeability), adhesion, and electrochemical impedance.    Discrepancies between studies may arise for a number of reasons including differences in polymer chemistries, test methods, and conditions.   In order to develop a mechanistic model specific to a particular chemistry, 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 implications of formulation choices, e.g. pigment volume concentration (PVC) and extender particle size, were also investigated.  The findings of these studies were then leveraged into development of a next generation, styrenated acrylic direct to metal (DTM) resin capable of being formulated at < 50g/L VOC.


Dr. Allen Bulick is the Technical Manager of EPS’ Industrial & Construction groups focusing on polymer design and formulation for a variety of applications including direct to metal, industrial wood, roof coatings, and pressure sensitive adhesives.  His background includes formulation science, and small molecule and polymer synthesis across several industries including Coatings, Electronic Materials, and Oil & Gas.  Allen graduated with a PhD in Chemical Engineering from Texas A&M University.