Experimental and Theoretical Evaluation of the Solubility/Insolubility of Spruce Xylan (Arabino Glucuronoxylan)
Journal article, 2019

© 2019 American Chemical Society. The molecular solubility of softwood arabinoglucuronoxylan (AGX) has been thoroughly investigated, and it has been shown that the chemical and physical structures of the extracted hemicellulose are not significantly influenced by different purification steps, but a transient molecular solubility of AGX was observed in aqueous media at low concentrations (1 g/L) when the dissolved macromolecules had a hydrodynamic diameter of up to 10 nm. A phase separation was detected when the concentration was increased to 15 g/L leading to an association of the smaller molecules into fractal structures with a considerably larger diameter, even though the dispersions were still transparent to ocular inspection. Dynamic Light Scattering and Cryo-Transmission Electron Microscopy showed dimensions in the range of 1000 nm. The phase separation of the sample was further characterized by estimating the χ-interaction parameter of AGX in water using the Flory-Huggins theory, and the results supported that water is a poor solvent for AGX. This behavior is crucial when films and hydrogels based on these biopolymers are made, since the association will dramatically affect barrier and mechanical properties of films made from these materials.

Author

Saina Kishani

Royal Institute of Technology (KTH)

Wallenberg Wood Science Center (WWSC)

Alfredo Escalante

University of Guadalajara

Guillermo Toriz Gonzalez

University of Guadalajara

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

francisco Vilaplana

AlbaNova University Center

Wallenberg Wood Science Center (WWSC)

Paul Gatenholm

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Per Hansson

Uppsala University

L. Wagberg

Wallenberg Wood Science Center (WWSC)

Royal Institute of Technology (KTH)

Biomacromolecules

1525-7797 (ISSN) 1526-4602 (eISSN)

Vol. 20 3 1263-1270

Subject Categories

Inorganic Chemistry

Physical Chemistry

Other Chemistry Topics

DOI

10.1021/acs.biomac.8b01686

PubMed

30689362

More information

Latest update

7/12/2019