10.1021/acssuschemeng.8b05427.s001
Kelechukwu
N. Onwukamike
Kelechukwu
N.
Onwukamike
Laurine Lapuyade
Laurine
Lapuyade
Laurence Maillé
Laurence
Maillé
Stéphane Grelier
Stéphane
Grelier
Etienne Grau
Etienne
Grau
Henri Cramail
Henri
Cramail
Michael A.R. Meier
Michael A.R.
Meier
Sustainable Approach for Cellulose Aerogel Preparation
from the DBU–CO<sub>2</sub> Switchable Solvent
American Chemical Society
2019
morphology
cellulose-based aerogels
cellulose concentration
coagulation approach
chemical modification
surface areas
cellulose aerogels
DBU
preparation procedure
XRD
4.5 μ m
macroporous cellulose network
processing conditions
Cellulose Aerogel Preparation
aerogel characteristics
pore size
2θ diffraction peak
SEM
Sustainable Approach
scanning electron microscopy
superbase
solubilization
pore sizes
crystal structure
porosity values
Density values
BET equation
N 2 adsorption
processing parameters
X-ray diffraction
2019-01-04 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Sustainable_Approach_for_Cellulose_Aerogel_Preparation_from_the_DBU_CO_sub_2_sub_Switchable_Solvent/7599761
We
report a sustainable and easy approach for the preparation of
cellulose-based aerogels from the DBU–CO<sub>2</sub> switchable
solvent system via a solubilization and coagulation approach followed
by freeze-drying. The easy, fast, and mild solubilization step (15
min at 30 °C) allows for a rapid preparation procedure. The effect
of various processing parameters, such as cellulose concentration,
coagulating solvent, and the superbase, on important aerogel characteristics
including density, porosity, pore size, and morphology, were investigated.
Density values obtained ranged between 0.05 and 0.12 g/cm<sup>3</sup>, with porosity values between 92% and 97%. The morphology of the
obtained cellulose aerogels was studied using scanning electron microscopy
(SEM) showing a random and open large macroporous cellulose network
with pore sizes ranging between 1.1 and 4.5 μm, depending on
the processing conditions. In addition, specific surface areas determined
by N<sub>2</sub> adsorption applying the BET equation ranged between
19 and 26 m<sup>2</sup>/g. The effect of the coagulating solvent and
superbase on the crystallinity was investigated using X-ray diffraction
(XRD) showing an amorphous crystal structure with a broad 2θ
diffraction peak at 20.6°. In addition, no chemical modification
was observed in the prepared aerogels from infrared spectroscopy.
Finally, the recovery and reuse of the solvent system was demonstrated,
thus making the process more sustainable.