1. Effects of supercritical carbon dioxide processing on the properties of chitosan–alginate membranes.
- Author
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Bueno, Cecilia Zorzi, Moraes, Ângela Maria, de Sousa, Hermínio C., and Braga, Mara Elga Medeiros
- Subjects
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CHITOSAN , *SUPERCRITICAL carbon dioxide , *ARTIFICIAL membranes , *ALGINATES , *SURGICAL dressings , *POROSITY - Abstract
Chitosan–alginate membranes with different porosities designed to be used as wound dressings or scaffolds were processed in supercritical CO 2 (scCO 2 ) with the aim of improving their physicochemical properties. The membranes were characterized before and after processing at 100 or 300 bar and 45 °C for 2 h with a depressurization rate of 5 bar/min. The results show that after processing, thickness, real density and porosity increased up to 68%, 100% and 167%, respectively, and surface area decreased up to 47%. Because of changes in structure, water vapor sorption and permeability increased up to 53% and 84%, respectively. Stabilization of the chitosan–alginate complex was noticed after processing with scCO 2 according to thermal analysis. The results indicate that supercritical CO 2 processing made the membranes more adequate for use as wound dressings. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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