Porous structures from bio-based polymers via supercritical drying

Abstract

Natural biobased polymers (biopolymers or biomacromolecules) such as polysaccharides, proteins, and polylactic acid derived from plant and animal sources are interesting materials due to their abundance, renewability, low cost, biodegradability, biocompatibility, and interesting chemistry. Many biopolymers can be induced to form gels consisting of a solvent trapped within the interstitial spaces of a three-dimensional polymeric network. The use of supercritical drying to remove the solvent contained within the gels without collapsing its threedimensional polymeric network provides unique highly porous materials known as aerogels. Biopolymer aerogels are a special class of lightweight highly porous structured materials that are of interest for their low densities, high surface areas, low heat conductivities, and mechanical strength. These aerogels are being investigated for in applications such as component separation, absorbents, catalysts and supports for chemical reactions, drug delivery, and scaffolds for tissue engineering. This chapter summarizes the latest research examining the preparation and properties of highly porous biobased aerogel structures via supercritical drying.