Revisiting the dissolution of cellulose in H

Anisotropy Cellulose dissolution DWS Liquid crystalline phase PTssNMR Phosphoric acid cryo-TEM

Journal

Carbohydrate polymers
ISSN: 1879-1344
Titre abrégé: Carbohydr Polym
Pays: England
ID NLM: 8307156

Informations de publication

Date de publication:
15 Jan 2021
Historique:
received: 25 02 2020
revised: 06 07 2020
accepted: 15 09 2020
entrez: 13 11 2020
pubmed: 14 11 2020
medline: 14 11 2020
Statut: ppublish

Résumé

Cellulose can be dissolved in concentrated acidic aqueous solvents forming extremely viscous solutions, and, in some cases, liquid crystalline phases. In this work, the concentrated phosphoric acid aqueous solvent is revisited implementing a set of advanced techniques, such as cryo-transmission electronic microscopy (cryo-TEM), polarization transfer solid-state nuclear magnetic resonance (PTssNMR), and diffusing wave spectroscopy (DWS). Cryo-TEM images confirm that this solvent system is capable to efficiently dissolve cellulose. No cellulose particles, fibrils, or aggregates are visible. Conversely, PTssNMR revealed a dominant CP signal at 25 °C, characteristic of C-H bond reorientation with correlation time longer than 100 ns and/or order parameter above 0.5, which was ascribed to a transient gel-like network or an anisotropic liquid crystalline phase. Increasing the temperature leads to a gradual transition from CP to INEPT-dominant signal and a loss of birefringence in optical microscopy, suggesting an anisotropic-to-isotropic phase transition. Finally, an excellent agreement between optical microrheology and conventional mechanical rheometry was also obtained.

Identifiants

DOI: 10.1016/j.carbpol.2020.117122 PMID: 33183588
pubmed: 33183588
pii: S0144-8617(20)31295-9
doi: 10.1016/j.carbpol.2020.117122
pii:
doi:

Types de publication

Journal Article

Langues

eng

Sous-ensembles de citation

IM

Pagination

117122

Informations de copyright

Copyright © 2020 Elsevier Ltd. All rights reserved.

Auteurs

Luís Alves (L)

CIEPQPF, Department of Chemical Engineering, University of Coimbra, Pólo II - R. Silvio Lima, 3030-790 Coimbra, Portugal. Electronic address: luisalves@ci.uc.pt.

Bruno Medronho (B)

MED - Mediterranean Institute for Agriculture, Environment and Development, University of Algarve, Faculty of Sciences and Technology, Campus de Gambelas, Ed. 8, 8005-139 Faro, Portugal; FSCN, Surface and Colloid Engineering, Mid Sweden University, SE-851 70 Sundsvall, Sweden.

Alexandra Filipe (A)

CIEPQPF, Department of Chemical Engineering, University of Coimbra, Pólo II - R. Silvio Lima, 3030-790 Coimbra, Portugal.

Anabela Romano (A)

MED - Mediterranean Institute for Agriculture, Environment and Development, University of Algarve, Faculty of Sciences and Technology, Campus de Gambelas, Ed. 8, 8005-139 Faro, Portugal.

Maria G Rasteiro (MG)

CIEPQPF, Department of Chemical Engineering, University of Coimbra, Pólo II - R. Silvio Lima, 3030-790 Coimbra, Portugal.

Björn Lindman (B)

FSCN, Surface and Colloid Engineering, Mid Sweden University, SE-851 70 Sundsvall, Sweden; Division of Physical Chemistry, Department of Chemistry, Center for Chemistry and Chemical Engineering, Lund University, SE-221 00 Lund, Sweden.

Daniel Topgaard (D)

Division of Physical Chemistry, Department of Chemistry, Center for Chemistry and Chemical Engineering, Lund University, SE-221 00 Lund, Sweden.

Irina Davidovich (I)

Chemical Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.

Yeshayahu Talmon (Y)

Chemical Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.

Classifications MeSH