A sustainable freeze-drying route to porous polysaccharides with tailored hierarchical meso- and macroporosity.
Macromol Rapid Commun
; 36(8): 774-9, 2015 Apr.
Article
em En
| MEDLINE
| ID: mdl-25721151
ABSTRACT
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.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Polissacarídeos
/
Terc-Butil Álcool
/
Hidrogéis
Idioma:
En
Revista:
Macromol Rapid Commun
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Reino Unido