Deep eutectic solvents as sustainable and new-generation solvents show potential in the field of cellulose dissolution. Although these novel materials are tested for numerous industrial, environmental, and medical applications, little is known about the structural features of cellulose interacting with deep eutectic solvents. In this work, the interplay of cellulose is studied in two deep eutectic solvents: choline acetate mixed with urea and choline chloride mixed with urea using classical molecular dynamics simulations. Dissolution of cellulose in the studied liquids was not observed to be in agreement with experimental work from the literature. However, a slight swelling in the chloride, as compared to the acetate-based solvent, is apparent. A possible rationale might be found in the stronger hydrogen bonding of the chloride anion compared to the acetate anion with the hydrogen atoms of the cellulose. Moreover, chloride approaches the outer glucose units comparatively more, which could be interpreted as the onset of entering and thus dissolving the cellulose as was previously observed. Specific hydrogen bonds between all units are analyzed and discussed in detail.

1.
T.
Heinze
,
O. A.
El Seoud
, and
A.
Koschella
,
Cellulose Derivatives: Synthesis, Structure, and Properties
(
Springer
,
2018
).
2.
A.
Farrán
,
C.
Cai
,
M.
Sandoval
,
Y.
Xu
,
J.
Liu
,
M. J.
Hernáiz
, and
R. J.
Linhardt
, “
Green solvents in carbohydrate chemistry: From raw materials to fine chemicals
,”
Chem. Rev.
115
,
6811
6853
(
2015
).
3.
R.
Portela
,
C. R.
Leal
,
P. L.
Almeida
, and
R. G.
Sobral
, “
Bacterial cellulose: A versatile biopolymer for wound dressing applications
,”
Microbiol. Biotechnol.
12
,
586
610
(
2019
).
4.
T.
Liebert
,
Cellulose Solvents: For Analysis, Shaping and Chemical Modification
(
ACS Publications
,
2010
), pp.
3
54
.
5.
B.
Medronho
and
B.
Lindman
, “
Competing forces during cellulose dissolution: From solvents to mechanisms
,”
Curr. Opin. Colloid Interface Sci.
19
,
32
40
(
2014
).
6.
T.
Rosenau
,
A.
Potthast
,
I.
Adorjan
,
A.
Hofinger
,
H.
Sixta
,
H.
Firgo
, and
P.
Kosma
, “
Cellulose solutions in N-methylmorpholine-N-oxide (NMMO)–degradation processes and stabilizers
,”
Cellulose
9
,
283
291
(
2002
).
7.
C.
Zhang
,
R.
Liu
,
J.
Xiang
,
H.
Kang
,
Z.
Liu
, and
Y.
Huang
, “
Dissolution mechanism of cellulose in N,N-dimethylacetamide/lithium chloride: Revisiting through molecular interactions
,”
J. Phys. Chem. B
118
,
9507
9514
(
2014
).
8.
J.
Zhang
,
J.
Wu
,
J.
Yu
,
X.
Zhang
,
J.
He
, and
J.
Zhang
, “
Application of ionic liquids for dissolving cellulose and fabricating cellulose-based materials: State of the art and future trends
,”
Mater. Chem. Front.
1
,
1273
1290
(
2017
).
9.
S.
Velioglu
,
X.
Yao
,
J.
Devémy
,
M. G.
Ahunbay
,
S. B.
Tantekin-Ersolmaz
,
A.
Dequidt
,
M. F.
Costa Gomes
, and
A. A.
Pádua
, “
Solvation of a cellulose microfibril in imidazolium acetate ionic liquids: Effect of a cosolvent
,”
J. Phys. Chem. B
118
,
14860
14869
(
2014
).
10.
H.
Zhao
,
C. L.
Jones
,
G. A.
Baker
,
S.
Xia
,
O.
Olubajo
, and
V. N.
Person
, “
Regenerating cellulose from ionic liquids for an accelerated enzymatic hydrolysis
,”
J. Biotechnol.
139
,
47
54
(
2009
).
11.
B.
Xiong
,
P.
Zhao
,
K.
Hu
,
L.
Zhang
, and
G.
Cheng
, “
Dissolution of cellulose in aqueous NaOH/urea solution: Role of urea
,”
Cellulose
21
,
1183
1192
(
2014
).
12.
E. L.
Smith
,
A. P.
Abbott
, and
K. S.
Ryder
, “
Deep eutectic solvents (DESs) and their applications
,”
Chem. Rev.
114
,
11060
11082
(
2014
).
13.
B. B.
Hansen
,
S.
Spittle
,
B.
Chen
,
D.
Poe
,
Y.
Zhang
,
J. M.
Klein
,
A.
Horton
,
L.
Adhikari
,
T.
Zelovich
,
B. W.
Doherty
 et al, “
Deep eutectic solvents: A review of fundamentals and applications
,”
Chem. Rev.
121
,
1232
(
2020
).
14.
B. E.
Gurkan
,
E. J.
Maginn
, and
E. B.
Pentzer
, “
Deep eutectic solvents: A new class of versatile liquids
,”
J. Phys. Chem. B
124
,
11313
(
2020
).
15.
M.
Francisco
,
A.
van den Bruinhorst
, and
M. C.
Kroon
, “
New natural and renewable low transition temperature mixtures (LTTMs): Screening as solvents for lignocellulosic biomass processing
,”
Green Chem.
14
,
2153
2157
(
2012
).
16.
M.
Pan
,
G.
Zhao
,
C.
Ding
,
B.
Wu
,
Z.
Lian
, and
H.
Lian
, “
Physicochemical transformation of rice straw after pretreatment with a deep eutectic solvent of choline chloride/urea
,”
Carbohydr. Polym.
176
,
307
314
(
2017
).
17.
G. C.
Dugoni
,
A.
Mezzetta
,
L.
Guazzelli
,
C.
Chiappe
,
M.
Ferro
, and
A.
Mele
, “
Purification of Kraft cellulose under mild conditions using choline acetate based deep eutectic solvents
,”
Green Chem.
22
,
8680
8691
(
2020
).
18.
R.
Häkkinen
and
A.
Abbott
, “
Solvation of carbohydrates in five choline chloride-based deep eutectic solvents and the implication for cellulose solubility
,”
Green Chem.
21
,
4673
4682
(
2019
).
19.
H.
Ren
,
C.
Chen
,
Q.
Wang
,
D.
Zhao
, and
S.
Guo
, “
The properties of choline chloride-based deep eutectic solvents and their performance in the dissolution of cellulose
,”
BioResources
11
,
5435
5451
(
2016
).
20.
P.
Li
,
J. A.
Sirviö
,
A.
Haapala
, and
H.
Liimatainen
, “
Cellulose nanofibrils from nonderivatizing urea-based deep eutectic solvent pretreatments
,”
ACS Appl. Mater. Interfaces
9
,
2846
2855
(
2017
).
21.
Y.
Ma
,
Q.
Xia
,
Y.
Liu
,
W.
Chen
,
S.
Liu
,
Q.
Wang
,
Y.
Liu
,
J.
Li
, and
H.
Yu
, “
Production of nanocellulose using hydrated deep eutectic solvent combined with ultrasonic treatment
,”
ACS Omega
4
,
8539
8547
(
2019
).
22.
M. A.
Smirnov
,
M. P.
Sokolova
,
D. A.
Tolmachev
,
V. K.
Vorobiov
,
I. A.
Kasatkin
,
N. N.
Smirnov
,
A. V.
Klaving
,
N. V.
Bobrova
,
N. V.
Lukasheva
, and
A. V.
Yakimansky
, “
Green method for preparation of cellulose nanocrystals using deep eutectic solvent
,”
Cellulose
27
,
4305
4317
(
2020
).
23.
C.-W.
Lai
and
S.-S.
Yu
, “
3D printable strain sensors from deep eutectic solvents and cellulose nanocrystals
,”
ACS Appl. Mater. Interfaces
12
,
34235
34244
(
2020
).
24.
S. J.
Pike
,
J. J.
Hutchinson
, and
C. A.
Hunter
, “
H-bond acceptor parameters for anions
,”
J. Am. Chem. Soc.
139
,
6700
6706
(
2017
).
25.
Y.
Cao
,
J.
Wu
,
J.
Zhang
,
H.
Li
,
Y.
Zhang
, and
J.
He
, “
Room temperature ionic liquids (RTILs): A new and versatile platform for cellulose processing and derivatization
,”
Chem. Eng. J.
147
,
13
21
(
2009
).
26.
M.
Brehm
,
M.
Pulst
,
J.
Kressler
, and
D.
Sebastiani
, “
Triazolium-based ionic liquids: A novel class of cellulose solvents
,”
J. Phys. Chem. B
123
,
3994
4003
(
2019
).
27.
L.
Martínez
,
R.
Andrade
,
E. G.
Birgin
, and
J. M.
Martínez
, “
PACKMOL: A package for building initial configurations for molecular dynamics simulations
,”
J. Comput. Chem.
30
,
2157
2164
(
2009
).
28.
C. J.
Smith
,
D. V.
Wagle
,
N.
Bhawawet
,
S.
Gehrke
,
O.
Hollóczki
,
S. V.
Pingali
,
H.
O’Neill
, and
G. A.
Baker
, “
Combined small-angle neutron scattering, diffusion NMR, and molecular dynamics study of a eutectogel: Illuminating the dynamical behavior of glyceline confined in bacterial cellulose gels
,”
J. Phys. Chem. B
124
,
7647
7658
(
2020
).
29.
S.
Plimpton
, “
Fast parallel algorithms for short-range molecular dynamics
,”
J. Comput. Phys.
117
,
1
19
(
1995
).
30.
W. L.
Jorgensen
,
D. S.
Maxwell
, and
J.
Tirado-Rives
, “
Development and testing of the OPLS all-atom force field on conformational energetics and properties of organic liquids
,”
J. Am. Chem. Soc.
118
,
11225
11236
(
1996
).
31.
S. V.
Sambasivarao
and
O.
Acevedo
, “
Development of OPLS-AA force field parameters for 68 unique ionic liquids
,”
J. Chem. Theory Comput.
5
,
1038
1050
(
2009
).
32.
W.
Damm
,
A.
Frontera
,
J.
Tirado-Rives
, and
W. L.
Jorgensen
, “
OPLS all-atom force field for carbohydrates
,”
J. Comput. Chem.
18
,
1955
1970
(
1997
).
33.
E.
Roos
and
M.
Brehm
, “
A force field for bio-polymers in ionic liquids (BILFF) – part 1:[EMIm][OAc]/water mixtures
,”
Phys. Chem. Chem. Phys.
23
,
1242
(
2020
).
34.
E. S. C.
Ferreira
,
I. V.
Voroshylova
,
C. M.
Pereira
, and
M. N. D. S.
Cordeiro
, “
Improved force field model for the deep eutectic solvent ethaline: Reliable physicochemical properties
,”
J. Phys. Chem. B
120
,
10124
10137
(
2016
).
35.
J. E.
Lennard-Jones
, “
Cohesion
,”
Proc. Phys. Soc.
43
,
461
(
1931
).
36.
J. W.
Eastwood
,
R. W.
Hockney
, and
D. N.
Lawrence
, “
P3M3DP—The three-dimensional periodic particle-particle/particle-mesh program
,”
Comput. Phys. Commun.
19
,
215
261
(
1980
).
37.
S.
Nose
, “
Constant-temperature molecular dynamics
,”
J. Phys.: Condens. Matter
2
,
SA115
(
1990
).
38.
W. G.
Hoover
,
H. A.
Posch
,
B. L.
Holian
,
M. J.
Gillan
,
M.
Mareschal
, and
C.
Massobrio
, “
Dissipative irreversibility from Nosé’s reversible mechanics
,”
Mol. Simul.
1
,
79
86
(
1987
).
39.
M.
Brehm
and
B.
Kirchner
, “
TRAVIS—A free analyzer and visualizer for Monte Carlo and molecular dynamics trajectories
,”
J. Chem. Inf. Model.
51
,
2007
2023
(
2011
).
40.
M.
Brehm
,
M.
Thomas
,
S.
Gehrke
, and
B.
Kirchner
, “
TRAVIS—A free analyzer for trajectories from molecular simulation
,”
J. Chem. Phys.
152
,
164105
(
2020
).
41.
S.
Kaur
,
M.
Kumari
, and
H. K.
Kashyap
, “
Microstructure of deep eutectic solvents: Current understanding and challenges
,”
J. Phys. Chem. B
124
,
10601
10616
(
2020
).
42.
K. R.
Harris
, “
Temperature and pressure dependence of the viscosity of the ionic liquid 1-butyl-3-methylimidazolium acetate
,”
J. Chem. Eng. Data
65
,
804
813
(
2020
).
43.
H. F. D.
Almeida
,
H.
Passos
,
J. A.
Lopes-da-Silva
,
A. M.
Fernandes
,
M. G.
Freire
, and
J. A. P.
Coutinho
, “
Thermophysical properties of five acetate-based ionic liquids
,”
J. Chem. Eng. Data
57
,
3005
3013
(
2012
).
44.
F.
Yang
,
X.
Wang
,
H.
Tan
, and
Z.
Liu
, “
Improvement the viscosity of imidazolium-based ionic liquid using organic solvents for biofuels
,”
J. Mol. Liq.
248
,
626
633
(
2017
).
45.
K. R.
Seddon
,
A.
Stark
, and
M.-J.
Torres
, “
Viscosity and density of 1-alkyl-3-methylimidazolium ionic liquids
,” in
Clean Solvents: Alternative Media for Chemical Reactions and Processing
(
American Chemical Society
,
2002
).
46.
I.
Bodachivskyi
,
U.
Kuzhiumparambil
, and
D. B. G.
Williams
, “
Catalytic valorization of native biomass in a deep eutectic solvent: A systematic approach toward high-yielding reactions of polysaccharides
,”
ACS Sustainable Chem. Eng.
8
,
678
685
(
2020
).
47.
S.
Gehrke
,
K.
Schmitz
, and
O.
Hollóczki
, “
Is carbene formation necessary for dissolving cellulose in ionic liquids?
,”
J. Phys. Chem. B
121
,
4521
4529
(
2017
).
48.
J.
Hoppe
,
R.
Drozd
,
E.
Byzia
, and
M.
Smiglak
, “
Deep eutectic solvents based on choline cation - Physicochemical properties and influence on enzymatic reaction with β-galactosidase
,”
Int. J. Biol. Macromol.
136
,
296
304
(
2019
).
49.
B.
Lindman
,
B.
Medronho
,
L.
Alves
,
C.
Costa
,
H.
Edlund
, and
M.
Norgren
, “
The relevance of structural features of cellulose and its interactions to dissolution, regeneration, gelation and plasticization phenomena
,”
Phys. Chem. Chem. Phys.
19
,
23704
23718
(
2017
).
50.
M.
Zhang
,
S.-C.
Wu
,
W.
Zhou
, and
B.
Xu
, “
Imaging and measuring single-molecule interaction between a carbohydrate-binding module and natural plant cell wall cellulose
,”
J. Phys. Chem. B
116
,
9949
9956
(
2012
).
51.
M.
Brehm
,
J.
Radicke
,
M.
Pulst
,
F.
Shaabani
,
D.
Sebastiani
, and
J.
Kressler
, “
Dissolving cellulose in 1, 2, 3-triazolium- and imidazolium-based ionic liquids with aromatic anions
,”
Molecules
25
,
3539
(
2020
).
52.
J.
Blasius
,
R.
Elfgen
,
O.
Hollóczki
, and
B.
Kirchner
, “
Glucose in dry and moist ionic liquid: Vibrational circular dichroism, IR, and possible mechanisms
,”
Phys. Chem. Chem. Phys.
22
,
10726
10737
(
2020
).
53.
S.
Gehrke
and
O.
Hollóczki
, “
N-heterocyclic carbene organocatalysis: With or without carbenes?
,”
Chemistry
26
,
10140
(
2020
).
54.
S.
Gehrke
and
O.
Hollóczki
, “
Are there carbenes in N-heterocyclic carbene organocatalysis?
,”
Angew. Chem., Int. Ed.
56
,
16395
16398
(
2017
).
55.
V.
Alizadeh
,
D.
Geller
,
F.
Malberg
,
P. B.
Sánchez
,
A.
Padua
, and
B.
Kirchner
, “
Strong microheterogeneity in novel deep eutectic solvents
,”
ChemPhysChem
20
,
1786
1792
(
2019
).

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