TY - JOUR
T1 - A Sustainable freeze-drying route to porous polysaccharides with tailored hierarchical meso- and macroporosity
AU - Borisova, Aleksandra
AU - De Bruyn, Mario
AU - Budarin, Vitaliy L.
AU - Shuttleworth, Peter S.
AU - Dodson, Jennifer R.
AU - Segatto, Mateus L.
AU - Clark, James H.
PY - 2015/4
Y1 - 2015/4
N2 - Bio-derived polysaccharide aerogels are of interest for a broad range of applications. To date, these aerogels have been obtained through the time- and solvent-intensive procedure of hydrogel fomation, solvent exchange, and scCO2 drying, which offers little control over meso/macropore distribution. A simpler and more versatile route is developed, using freeze drying to produce highly mesoporous polysaccharide aerogels with various degrees of macroporosity. The hierarchical pore distribution is controlled by addition of different quantities of t-butanol (TBA) to hydrogels before drying. Through a systematic study an interesting relationship between the mesoporosity and t-butanol/water phase diagram is found, linking mesoporosity maxima with eutectic points for all polysaccharides studied (pectin, starch, and alginic acid). Moreover, direct gelation of polysaccharides in aqueous TBA offers additional time savings and the potential for solvent reuse. This finding is a doorway to more accessible polysaccharide aerogels for research and industrial scale production, due to the widespread accessibility of the freeze drying technology and the simplicity of the method. Hierarchical polysaccharide aerogels with tailored meso/macropore structure are generated with a novel freeze-drying route. An interesting relationship between the water/t-butanol phase diagram and the porous network is discussed, and the role of the eutectic phase in tailoring the porosity is revealed. The route offers significant time and solvent savings and allows for solvent reuse.
AB - Bio-derived polysaccharide aerogels are of interest for a broad range of applications. To date, these aerogels have been obtained through the time- and solvent-intensive procedure of hydrogel fomation, solvent exchange, and scCO2 drying, which offers little control over meso/macropore distribution. A simpler and more versatile route is developed, using freeze drying to produce highly mesoporous polysaccharide aerogels with various degrees of macroporosity. The hierarchical pore distribution is controlled by addition of different quantities of t-butanol (TBA) to hydrogels before drying. Through a systematic study an interesting relationship between the mesoporosity and t-butanol/water phase diagram is found, linking mesoporosity maxima with eutectic points for all polysaccharides studied (pectin, starch, and alginic acid). Moreover, direct gelation of polysaccharides in aqueous TBA offers additional time savings and the potential for solvent reuse. This finding is a doorway to more accessible polysaccharide aerogels for research and industrial scale production, due to the widespread accessibility of the freeze drying technology and the simplicity of the method. Hierarchical polysaccharide aerogels with tailored meso/macropore structure are generated with a novel freeze-drying route. An interesting relationship between the water/t-butanol phase diagram and the porous network is discussed, and the role of the eutectic phase in tailoring the porosity is revealed. The route offers significant time and solvent savings and allows for solvent reuse.
KW - biological materials
KW - hierarchical materials
KW - material science
KW - polymers
KW - porous materials
UR - http://www.scopus.com/inward/record.url?scp=84927786477&partnerID=8YFLogxK
U2 - 10.1002/marc.201400680
DO - 10.1002/marc.201400680
M3 - Article
AN - SCOPUS:84927786477
SN - 1022-1336
VL - 36
SP - 774
EP - 779
JO - Macromolecular Rapid Communications
JF - Macromolecular Rapid Communications
IS - 8
ER -