Cellulose Nanocrystals as
building blocks for
innovative materials
Isabelle Capron,
Céline Moreau, Hervé Bizot and Bernard Cathala
UR1268 Biopolymères Interactions Assemblages,,
[email protected] [email protected]
Nantes - France.
200 nm
Context
Biomimetic
or model
assemblies
Biological
materials
Biobased
materials
Physical/
chemical
interactions
Envirt &
Eng & Eco
constraints
Adapted from Aizenberg and Fratzl, Adv Mat. 2009
Why « Nanoscale » ?
Nanoscale (1 to several hundreds of nm) allows the control or the elaboration of
properties (functionalities) intrinsically linked to the nano scale.
Plant cell walls and nanocellulose
Cellulose: most abondant biopolymer, biodegradable, sustainable, low density
Single microfibril
Nanocelluloses
The nanodimensions result in a high surface area and hence the powerful
interaction of these celluloses with surrounding species, such as water, organic and
polymeric compounds, nanoparticles and living cells.
According to the process of preparation three
main types of nanocellulose can be defined :
Nanofibrillated
cellulose
Cellulose
nanocrystal (CN)
Bacterial
nanocellulose
Klemm et al. Angew Chem 2011, 50, 5438
Nano celluloses (1): Nanofibrillated cellulose
1- High pressure homogenizers
2- Pretreated fibers by various chemical and enzymatic methods
Chemical method: TEMPO-Mediated Oxidation
(2,2,6,6-Tetramethylpiperidine-1-oxyl)
OH
CH2
NaOCl/NaBr
TEMPO
Na+
O=C
NaOCl/NaBr
TEMPO
Nano celluloses (2): Bacterial cellulose
Cellulose nanofibers
Synthesis by bacterial cell from low molecular weight compounds
Films/mats
Spheres
Tubes
Nano celluloses (3): Cellulose nanocrystals
Acid Hydrolysis of cellulose from cotton:
cellulose
H2SO4
nanocrystals
H2SO4 hydrolyses of amorphous regions.
OH are substituted by negatively charged
sulfate groups
Colloïdal stability
Roland et Roberts 1972
Nano celluloses (3): Cellulose nanocrystals
Cotton
Bacterial Cellulose
Cladophora
After extraction by acid hydrolysis
200nm x 6 nm
900nm x 7nm
3µm x 10nm
Morphology and functionnality can be tuned according to biological
origin, hydrolysis process, post treatment, etc…
Cellulose nanocrystals
A versatile building block for biobased nanomaterials
OH
• Electrostatic interactions
• Hydrogen bonds
• van der Waals
• Stiff nanorods with contrasted
surfaces
SO3-
010
1-10
110
100
CH
Cellulose nanocrystals
Multilayer thin films
Hydrogen bonds
van der Waals
OH
SO3-
010
1-10
CH2
110
100
Non-electrostatic interactions
with xyloglucan
Enzymatic
activity assay
Multilayered thin film CN/xyloglucan
OH
HO
OH
O
CH2
O
O
OH
OH
HO
O
H2C
OH
HO
OH
Fuc
OH
HO
H2C
O
O
O
O
H2C
OH
HO
O
O
O
O
OH
HO
H2C
O
O
O
HO
O
HO
Ara
OH
HO
OH
HO
X
L
X
G
Xyloglucan interacts strongly with
cellulose surface through van der
Waals and Hydrogen bonds
Rose and Bennett, Trends in Plant Science, 4 (1999) 176-183
Fleer, Polymers at Interface (1993)
Spin assisted elaboration of multilayered thin films
OH
HO
OH
O
CH2
O
O
OH
OH
HO
O
OH
Fuc
H2C
OH
HO
O
OH
HO
H2C
O
O
O
O
H2C
OH
HO
O
O
O
OH
HO
H2C
O
O
O
HO
O
HO
Ara
OH
HO
OH
HO
X
X
G
Xyloglucan
XG
Cotton CN
Si wafer
L
CN
XG
Cerclier,C. Cousin F., Bizot H., Moreau C. and Cathala B., Langmuir, 26(22), 17248–1725 2010
Multilayered thin CN/xyloglucan film : growth patterns
5 g/L
Xyloglucan viscosity curves
10 g/L
1 g/L
C**
0.5 g/L
C*
Semi-diluted regime C<C**
120
XG 0.5 and 1g/L
Thickness (nm)
Thickness (nm)
120
100
80
60
40
20
0
Entangled regime C>C**
0
2
4
6
8
(CN/XG) deposit
n
Linear growth = 16 nm/bilayer
XG 10g/L
100
80
60
XG 5g/L
40
20
0
0
2
4
6
(CN/XG) deposit
n
No growth
8
Multilayered thin CN/xyloglucan film : growth pattern
Semi diluted regime C<C**
120
XG 0.5 and 1g/L
Thickness (nm)
Thickness (nm)
120
100
80
60
40
20
0
Entangled regime C>C**
0
2
4
6
8
(CN/XG) deposit
n
XG 10g/L
100
80
60
XG 5g/L
40
20
0
0
2
4
6
8
(CN/XG) deposit
n
XG
Cellulose
Adhesive
Under shearing
(spinning)
Under shearing
(spinning)
Anti-adhesive
Multilayered thin CN/xyloglucan film : growth pattern
Xyloglucan = 1g/L; CN = 5 g/L
n=3
Thickness (nm)
150
n=7
n=5
n=3
100
n=8
n=1
50
Slope growth :
16 nm/bilayer
n=6
n=4
n=2
0
0
2
4
6
Si
8
(CN/XG) deposit
n
C. Cerclier et al. Langmuir, 26(22), 17248–1725 2010
Influence of the dipping parameters
Structural colors with increasing thickness
Air
Thin film (n1)
Reflective support (ns)
Constructive interference
Destructive interference
Multilayers with
biopolymers
Enzyme
?
Detection of cellulase activity
1)
2) Rinsing and drying
0.600 nkat/mL
0.240 nkat/mL
0.120 nkat/mL
0.060 nkat/mL
0.024 nkat/mL
0.006 nkat/mL
time
0 min
3min
5 min
10 min
15 min
The method is 200 times more sensitive than a
standard detection method (Nelson)
B. Cathala & C. Cerclier. Patent N° FR 1055529 (2010)
C. Cerclier et al. Advanced Materials (2011). 23: 3791–3795
Multilayered thin films as model heterogeneous catalaysis
Hydrogen +
van der Waals
interactions
+ cellulose
nanocrystals (CN)
+++++++++++
+ Xyloglucan (XG)
+++++++++++
+++++++++++
Multilayered thin films CN-XG
+++++++++++
Anchoring layer (PAH)
Electrostatic +
Hydrogen +
van der Waals
interactions
+ mixture of CN/XG
+++++++++++
+ PAH
+++++++++++
+++++++++++
+++++++++++
+++++++++++
+++++++++++
Multilayered thin films PAH-CN/XG
Neutrons reflectivity
Air n=1
n1
Substrat ns
-Kiessig fringes give an
indication on the thickness of
the layer
- Determination of the chemical
composition of the films
Neutrons reflectivity
+++++++
+++++++
thicknessdry (nm)
thicknessswollen (nm)
Swelling ratio
+++++++
+++++++
(C5 - XG1)4
(PAH - C5/XG1)2
65
126
1.9
53
186
3.4
0.45
0.45
0.10
0.27
0.62
0.11
Volume fractions:
CN
XG
Air
Cerclier C., et al Biomacromolecules (2013) dx.doi.org/10.1021/bm400967e
Degradation study by QCM-D
(Quartz Crystal Microbalance with Dissipation)
Amplitude
time
Δf & ΔD
ΔfΔD
ΔD
Δf
Time
Mass coupled to the surface
+
viscoelasticity of the coupled layer
Degradation study by QCM-D
t0
t0
t1
t2
ΔFplateau
Dplateau
D7 (10-6)
F7/7 (Hz)
Dmax
tplateau
time (min)
Cerclier C., et al Biomacromolecules (2013) dx.doi.org/10.1021/bm400967e
Degradation study by QCM-D
Df3/3
Enz = 50 µg.mL-1
DD3/3
(PAH-C5/XG1)2
2,5
+++++++
+++++++
2
+++++++
Pente
slope
1,5
Time (min)
Df3/3
Enz = 208 µg.mL-1
DD3/3
1
0,5
+++++++
0
0
100 200 300 400 500 600 700
[Enz] µg/mL
(C5-XG1)4
Hydrolysis is faster when CN and XG are mixed
Time (min)
Cerclier C., et al Biomacromolecules (2013) dx.doi.org/10.1021/bm400967e
Degradation study by QCM-D
+++++++
(C5-XG1)4
(PAH-C5/XG1)2
+++++++
+++++++
+++++++
PAH
XG
CNC
PAH
The critical parameter of hydrolysis is the swelling level due to cross-links
Cerclier C., et al Biomacromolecules (2013) dx.doi.org/10.1021/bm400967e
Cellulose nanocrystals
Hydrophobic character
Dispersion via
electrostatic repulsions:
Sulfate ester groups
OH
SO3-
010
1-10
CH
110
100
Hybrid Multilayered
thin films for
advanced materials
Toward new functionnality : CN/SWNT complex
Single Wall Carbon Nanotubes (SWNTs)
Dimensions
length = several µm; section ~1 nm
Unique properties
Electrical, optical, mechanical…
SWNTs polymer nanocomposites
Specific properties
Multifonctionality
Challenges
Dispersion : Insolubility in most solvents
Covalent fonctionalization : loss of SWNTs properties
Sonication with dispersants : surfactant, polymers, biomolecules…
Structuration
Homogeneous repartition
1D, 2D organization
SWNTs dispersion with Cellulose Nanocrystals
SWNTs / CNs-H2O
O.D. at 891nm
Ultrasounds
Increasing time of ultrasound
Extinction coefficient
α = 2.14 mL/mg.mm
SWNTs Concentration up to 0.4mg/mL
Maximum dispersion yield = 70%
SWNTs/Cellulose mass ratios up to 0.15:1
Olivier C., Langmuir, 28 (34), pp 12463–12471, 2012
SWNTs dispersion with Cellulose Nanocrystals
SWNTs/CNs dispersion
0.030
0.025
Raman exc. 1064nm
(E1 excitation)
0.30
0.25
0.20
0.015
PL exc. = 670nm
PL exc. = 810nm
(E2 excitation)
0.15
0.010
0.10
0.005
Raman intensity (a.u.)
RBM
0.020
PL intensity (a.u.)
0.35
G-band
0.05
0.000
0.00
900
1000
1100
1200
1300
1400
Wavelenght (nm)
Well isolated semi-conducting SWNTs
28
SWNTs dispersion with Cellulose Nanocrystals : Morphology
Cellulose nanocrystals : anisotropic materials
Contrasted surfaces
010
Hydrophilic groups accessibility
1-10
60
More
Hydrophobic
More
hydrophilic
110
100
55
50
hydrophobic plan
45
40
35
30
110
1-10
100
SWNT
010
K. Mazeau Carbohydr. Polym. 2011, 84, 524
« Free »
section of
SWNT
Elaboration of multilayered thin films
Growth pattern
Linear growth
18 nm/bilayer
17 nm/bilayer
SWNT/CN interaction does not significantly affect
the adsorption process and the film growth
Elaboration of multilayered thin films
Excitation at 1064nm
Raman signature of SWNTs is obtained from the films containing SWNT/CN dispersions
Elaboration of multilayered thin films
Excitation at 1064nm
A constant number of SWNTs are incorporated into each CN layer
Elaboration of multilayered thin films
Raman/Luminescence exc: 1064nm
Luminescence
8
2
Luminescence : well isolated SWNTs
Evaluation of electrical properties
SEM image of a 8 bi-layer film
Electrical conductivity :
40 S/m (+/- 20 S/m)
1 μm
(4-point probe measurements)
Percolation of SWNTs
Cellulose nanocrystals
Hydrophobic character
Stiff nanorods with
contrasted surfaces
OH
SO3-
010
1-10
CH
110
100
Pickering emulsions
Cellulose nanocrystals based Pickering emulsions
Emulsion Definition:
Metastable system of two immiscible liquids
Macroscopic phase separation
Cellulose nanocrystals based Pickering emulsions
3 main types of interfacial stabilisation
mono- layer
Surfactant
molecule
multi- layered
associated
molecules
oil
oil
Surface active agents at an oil / water interface
Colloidal particles
Pickering emulsion
Pickering, S. U. (1907). Journal of Chemical society 91: 2001.
Cellulose nanocrystals based Pickering emulsions
Size and wetting parameters
  900
  900
  90 0
for g = 50 mN/m
hydrophilic
Particles
E = π . r² . γ (1±cos)²
Particles can be considered
irreversibly adsorbed.
Hydrophobic
Particles
Oil in water emulsion
B.P. Binks Current Opinion in Colloid & Interface Science 7 (2002) 2141
Cellulose nanocrystals based Pickering emulsions
hexadecane
aqueous phase
emulsification
suspension of cellulose
nanocrystals
10 m
Highly stable armored droplets
50µm
Droplets stabilized by BCN
with double staining
(BODIPY and calcofluor).
1 µm
Scanning electron micrographs of styrene Pickering emulsion
stabilized by BCN and polymerized using thermal initiator
Kalashnikova, I et al Biomacromolecules 13 (1), pp 267–275 (2012)
Capron et al. Patent N° 1055836 (2010)
Cellulose nanocrystals based Pickering emulsions
highly stable emulsions
• dispersion
• concentration creaming process
• time over a year
• temperature 4°C, 40°C or up to 2 hours at
80°C
• pH from 1 to 12
18
16
14
12
10
8
6
4
2
0
0,1
1
10
diametre (µm)
100
Cellulose nanocrystals : amphilic material?
Hydrophilic groups accessibility
010
60
More
Hydrophobic
More
hydrophilic
55
50
45
40
35
30
110
1-10
100
010
K. Mazeau Carbohydr. Polym. 2011, 84, 524
1-10
110
100
Emulsion vs concentration : Exemple of BCN
Diameter
Emulsion volume
1000
900
60
50
700
D(3 ,2 ) (µ m)
Vol d'émulsion (µL)
800
600
500
400
300
200
40
30
20
10
100
0
0
0
1
2
3
4
5
6
7
8
9
0
10
1g/L
4
6
8
10
conc (g/L)
conc (g/L)
0,8g/L
2
1,5g/L
2g/L
5g/L
7 g/L
10 m
Optical microscopy
Limited coalescence process
Decreasing interface area
+
emulsion
suspension oil
Not covered
droplets
droplets
stabilised
The drop size is controlled by the amount of particles introduced
Cellulose nanocrystals based Pickering emulsions
Emulsions prepared varying concentration
0.1
0.2
0.3
0.5
0.8
1
1.2
1.5
2
3
4
5 (g/L)
0,9
emulsion ratio (%)
% hexadecane
After centrifugation 4000g
0,8
0,7
0,6
74% of hexadecane
Close packing conditions
0,5
0,4
0,3
0,2
0.1
0.2
0.3
0.5
0.8
1
1.2
1.5
2
3
4
5 (g/L)
0,1
0
0
1
2
3
4
5
concentration BCN (g/L)
BCN concentration (g/L)
Kalashnikova, I.; Bizot, H.; Cathala, B.; Capron, I. Langmuir, 27, 7471–7479(2011)
6
Cellulose nanocrystals based Pickering emulsions
Inverse drop diameter is proportionnal to the amount of particules to
stabilize oil
0,25
Limited
coalescence
1/D
(µm-1)
1/D (µm-1)
0,2
0,15
0,1
Changing covering mode
0,05
0
0
2
4
6
8
10
12
14
mp (mg per mL of hexadecane)
mp (mg
de NC / ml hexadecane)
2 covering modes
Cellulose nanocrystals based Pickering emulsions
Stability with partial coverage of the droplet surfaces
1
Coverage :
0,8
Coverage
SCN/Sdroplets
0,6
0,4
0,2
0
0
5
10
CN (g/L)
15
Cellulose nanocrystals based Pickering emulsions
Stability with partial coverage of the droplet surfaces
1
Coverage :
0,8
Coverage
SCN/Sdroplets
0,6
0,4
0,2
0
0
5
10
15
CN (g/L)
500nm
500nm
Kalashnikova, I.; et al. Langmuir, 27, 7471–7479(2011)
Source and aspect ratio
Cotton
Bacterial Cellulose
1µm
100 nm
1µm
100nm
Cladophora
1µm
100nm
Kalashnikova, Bizot, Bertoncini, Cathala and Capron. Soft Matter 2013
Source and aspect ratio
1.4
CCN
1.2
BCN
ClaCN
Low concentration domain:
Isolated beads
coverage ratio
1
0.8
0.6
0.4
0.2
0
0
2
4
6
8
10
12
14
16
CCN
BCN
ClaCN
mp (mg / mL hexadecane)
High concentration domain:
Interconnected network
Kalashnikova, Bizot, Bertoncini, Cathala and Capron. Soft Matter 2013
High internal phase emulsion … oil as a gel
+ oil
50%
interfaces
deformation is
achieved without
coalescence
high drop interface
stability
75%
10µm
Pickering
MIPE
60%
20%
Liquid emulsion
HIPE
Soft gel
85%
Hard gel
Patent Capron, Bizot Cathala 2011
Kalashnikova, et al Biomacromolecules 2013, 14, 291−296
From emulsion to foams
Emulsification
Centrifugation
Freeze drying
1 µm
+
cyclohexane
10 µm
Tasset S et al, et al submitted
Cellulose nanocrystals
Electrostatic interactions:
films with cationic
polyelectrolytes and
dispersion.
OH
SO3-
010
1-10
Stiff nanorods with
contrasted surfaces :
Hybrid nanobricks and
Pickering emulsion
CH
110
100
Hydrogen bonds
van der Waals interactions:
Multilayered thin films with
xyloglucan