Functional polymer films via Layer-by-Layer (LbL) assembly

Layer-by-Layer (LbL) assembly of oppositely charged polymers into films and coatings is a versatile way of surface modification, and fabrication of nanostructured thin films. The LbL approach has been used in fabrication of advanced materials, for instance, surface active biomedical devices, self-healing coatings, flexible batteries, nanofiltration membranes, anti-corrosion coatings etc. The breadth of applications demands novel polymers and optimized processing conditions to achieve desired functionality. In this project you will use novel polymerized ionic liquids (PILs) that were synthesized in our lab to prepare LbL films by dip coating (Figure 1).

Figure 1 - Sequential deposition of oppositely charged polyionic liquids (PILs) towards fabrication of nanostructured thin films.
Figure 1 - Sequential deposition of oppositely charged polyionic liquids (PILs) towards fabrication of nanostructured thin films.

In the first stage, by using Ellipsometry, the film assembly/disassembly conditions will be optimized, specifically the effect of salt, counter ions, temperature and solvent composition.

In the second stage, the surface morphology, internal film structure (Atomic Force Microscopy and Electron Microscopy) and film response (self-healing, swelling) to external stimuli will be characterized.

A fundamental understanding of these LbL films from PILs will help in designing advanced materials, specifically, nanofiltration and ion-conducting membranes. For more science on responsive films see these articles in Chemistry of Materials and Macromolecules.