Polyfoam: Foam-Templated Microcellular Polymers

Langmuir. 2020 Jul 14;36(27):7868-7878. doi: 10.1021/acs.langmuir.0c00932. Epub 2020 Jul 1.

Abstract

High internal phase emulsion (HIPE) templating has been developed as a robust method for the synthesis of porous polymers with designed porosity and void size. However, it has low starting material efficiency, requiring the removal of over 74% of the starting material to form interconnected porous structures. Foam templating methods attempt to resolve this issue by replacing the internal liquid phase with a gas phase. The current challenge for foam templating is to reach small void sizes (<100 μm), especially when using free-radical polymerization. We use a rapid gas dispersion method to form foam-templated hydrogels, which is an energy-effective method in comparison to the typical HIPE templating approach. We report hydrogels with an average void diameter of 63 μm at 70% porosity. The morphology and properties of foam-templated hydrogels are evaluated to show comparability to the HIPE-templated hydrogels of the same material.