Figure 1: NFC fibrils imaged through SEM (a) and TEM (b)
Ethanol content (wt.%) |
α |
RM |
|
0 |
2.13 × 1015 |
1.65 × 1012 |
|
50 |
6.95 × 1014 |
-3.07 × 1010 |
|
60 |
1.04 × 1014 |
-2.29 × 1011 |
|
75 |
3.82 × 1013 |
-4.79 × 1011 |
Table 1:Calculated cake specific resistance (α) membrane specific resistance (RM) and for filtration of NFC suspensions with different ethanol contents
Suspensions’ ethanol content (wt.%) |
Drying conditions* |
Grammage |
Apparent density |
Porosity |
Tensile index |
Elongation (%) |
Young’s modulus (GPa) |
Bending stiffness |
ISO Brightness |
ISO Opacity (%) |
Transparency |
Scattering coefficient (cm2 g-1) |
0 |
Standard |
47.5±2.6a |
1.3±0.05a |
18.8±3.0a |
71.6±8.3a |
1.7±0.3a |
6.4±0.4a |
72.5±0.2a |
36.42±1.09 |
26.91±2.51 |
83.81±1.61 |
0.04±0.07 |
Oven |
46.9±1.3a |
1.3±0.06a |
18.8±3.6a |
124.0±15.4b |
6.1±2.4b |
5.9±1.4d |
76.3±0.1e |
36.01±1.03 |
47.03±1.93 |
71.96±1.31 |
2.00±0.02 |
|
50 |
Standard |
51.8±0.5b |
1.3±0.05a |
18.8±3.3a |
75.4±11.8a |
1.6±0.5a |
6.9±0.6a |
85.0±1.3b |
38.19±0.48 |
26.49±1.14 |
83.43±0.78 |
0.14±0.01 |
Oven |
50.3±0.6b |
1.1±0.01b |
31.3±0.9c |
99.7±13.2c |
6.5±1.4b |
4.5±0.8e |
88.8±0.1f |
41.67±0.57 |
39.70±1.19 |
75.22±0.65 |
3.41±0.03 |
|
60 |
Standard |
50.3±1.0b |
1.2±0.01b |
25.0±0.8b |
62.2±7.1b |
1.5±0.4a |
6.2±0.5b |
91.3±0.2c |
40.15±0.60 |
27.30±1.32 |
82.86±0.92 |
2.91±0.21 |
Oven |
50.3±0.8b |
0.9±0.01b |
43.8±0.5d |
87.3±6.2d |
6.8±0.6b |
3.3±0.1f |
97.5±0.2g |
69.31±0.65 |
71.20±2.03 |
47.52±0.10 |
15.74±0.14 |
|
75 |
Standard |
51.5±1.7b |
1.1±0.05b |
31.3±3.0c |
70.411.3a |
2.1±0.6a |
5.4±0.2c |
82.5±0.3d |
43.16±3.36 |
36.29±4.13 |
72.92±3.19 |
6.49±0.99 |
Oven |
51.0±0.1b |
0.8±0.01b |
50.0±0.7e |
92.2±7.1e |
6.3±1.1b |
3.2±0.1f |
110.0±0.3h |
58.01±2.21 |
69.52±3.74 |
48.83±2.45 |
15.05±0.85 |
Table 2:Mechanical and optical characterization of NFC films produced from NFC suspensions with different ethanol compositions
Drying conditions: Standard is air dried overnight at 22ºC and 50% RH; Oven is oven dried at 70ºC for 4 hours Means at the same column with different superscript letters are significantly different (p < 0.05).
Ethanol content (wt.%) |
Drying conditions |
WVTR |
|
Porosity |
0 |
Standard |
137.82 |
|
18.8 |
50 |
137.52 |
|
18.8 |
|
60 |
134.83 |
|
25.0 |
|
75 |
207.48 |
|
31.3 |
|
0 |
Oven |
163.83 |
|
18.8 |
75 |
291.19 |
|
50.0 |
Table 3:Mechanical and optical characterization of NFC films produced from NFC suspensions with different ethanol compositions
Drying conditions: Standard is air dried overnight at 22ºC and 50% RH; Oven is oven dried at 70ºC for 4 hours Means at the same column with different superscript letters are significantly different (p < 0.05).
Figure 1: NFC fibrils imaged through SEM (a) and TEM (b)
Figure 2: Monitorization of drainage during the manufacture of films from NFC suspensions with different ethanol contents: a.) total filtration time; b.) zoom in of the first 20 minutes of filtration
Figure 3: Linear regression of At/V as function of V/A in an NFC aqueous suspension filtration process
Figure 4: Films produced from a 75wt.% ethanol NFC suspension (left) and from a purely aqueous NFC suspension (right) dried under standard conditions
Figure 5: Transferred water vapor as a function of test time for NFC films produced from different ethanol content NFC suspensions
Tables at a glance
Figures at a glance