SusChEM: Collaborative Research: Identification of the critical length scales and chemistries responsible for the anti-fouling properties of heterogeneous surfaces

Tufts University, Medford MA

Investigators

Abstract

In this project funded by the Environmental Chemical Sciences Program in the Chemistry Division at the National Science Foundation, Professors Meagan S. Mauter of Carnegie Mellon University and Ayse Asatekin of Tufts University characterize the fundamental mechanisms of foulant adhesion to naturally occurring surfaces. The ability to prevent soiling of a surface (prevent fouling) has many practical applications in both biomedical and marine applications. This research is leading to a new class of fouling resistant surfaces that enable energy savings. The ability to use anti-fouling membranes (i.e., filters that do not become clogged) to remove salt from sea water (desalinization) is also a potential benefit of this research. Two graduate and several undergraduate students involved in this research gain interdisciplinary knowledge and skills, and disseminate their work through publications and presentations. This work involves polymer synthesis, colloidal force and deposition experiments, and modeling to evaluate the relative importance of domain size, domain hydrophobicity/hydrophilicity contrast, and domain chemistry in determining foulant adsorption. A library of copolymer films with surface heterogeneity on the length scale of 1 to 10 nm are synthesized and characterized. The material properties are used to model the attachment efficiency of colloids to these heterogeneous surfaces using three models of increasing complexity. These models are validated using colloidal force microscopy and mass-based deposition measurements using a quartz crystal microbalance with dissipation monitoring. Finally, this project explores the role of nanopatterning on colloidal release as a function of shear velocity. Both Professors Mauter and Asatekin are active advocates of broadening the participation of women in science and engineering fields, and incorporate this research into their classes which includes topics in environmental policy, polymer science, and separations.