Susan Dong
Research Fellow
Stepan
Susan Dong is a Research Fellow at Stepan Company. She holds a Ph.D. in physical chemistry and a master’s degree in polymer chemistry. She has been working on new surfactant and additive technologies for over 20 years in various industrial applications. She is a co-inventor for more than 20 patent applications.
Novel Fluoro-Free and Silicone-Free Blocking Resistance Additives for Waterborne Coatings
Fluorosurfactants are often used in waterborne coatings to reduce surface defects and improve functional properties. However, there is a strong demand for alternatives due to their persistence in the environment and health concerns. Silicone surfactants are sometimes utilized but not without adverse effects. To the best of our knowledge, phosphate esters (typically used as wetting agents) have never been considered as suitable replacements for fluorosurfactants. However, the utility of phosphate esters in this area was serendipitously discovered by our team while exploring their surface properties as specialty coating additives. It was found that phosphate esters with a certain chemical structure can effectively address blocking in latex paint films, even offering improvements over the fluorosurfactant control. Proprietary technology was derived from these surprising findings, which will be described in this presentation. The evaluation techniques utilized to gain fundamental understanding of the performance and the resulting data will also be covered.