Superchaotropic Nano-ion Binding as a Gelation Motif in Cellulose Ether Solutions.
Angew Chem Int Ed Engl
; 62(3): e202210208, 2023 01 16.
Article
en En
| MEDLINE
| ID: mdl-36346946
Nanometer-sized anions (nano-ions) like polyoxometalates and boron clusters exhibit so-called superchaotropic behavior, which describes their strong binding to hydrated non-ionic matter in water. We show here that nano-ions, at millimolar concentrations, dramatically enhance the viscosity and induce gelation of aqueous solutions of non-ionic cellulose ethers (CEs), a class of widely utilized polymers known for their thickening and gel-forming ability. These phenomena arise from an interplay of attractive forces and repulsive electrostatic forces between CE-chains upon nano-ion binding. The attractive forces manifest themselves as aggregation of CE-chains into a physically crosslinked polymer network (gel). In turn, the electrostatic repulsions hamper the viscosity increase and gelation. Superchaotropic nano-ion binding emerges as a novel and general physical crosslinking motif for CE-solutions and exceeds by far the conventional thickening effects of classical salts and ionic surfactants.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Celulosa
/
Éter
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Año:
2023
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Alemania