Material | U-CNF | T-CNF | C-CNF | E-CNF | Source fibres | ||
---|---|---|---|---|---|---|---|
Surface modification | None | TEMPO oxidation | Carboxy-methylation | EPTMAC quaternization | None | ||
Degree of crystallinity (%) | 75 | 67 | 71 | 70 | 76 | ||
Fibril dimensions (nm) | |||||||
Fine | D | 5.7 ± 0.1 | 4.7 ± 0.9 | 4.9 ± 0.1 | 4.8 ± 0.1 | D: 16.2 ± 1.3 µm | |
L | 989 ± 256 | 892 ± 301 | 1127 ± 231 | 1020 ± 505 | |||
L/D | 173 | 191 | 228 | 213 | |||
Medium | D | 8.6 ± 0.1 | 7.8 ± 0.3 | 8.9 ± 0.2 | 7.6 ± 0.3 | L: 0.9 ± 0.1 mm | |
L | 1690 ± 640 | 1491 ± 125 | 1920 ± 321 | 1702 ± 124 | |||
L/D | 197 | 190 | 215 | 225 | |||
Coarse | D | 18.8 ± 1.4 | 15.4 ± 0.2 | 17.5 ± 0.1 | 16.30 ± 1.0 | L/D: 55.5 | |
L | 2768 ± 521 | 2168 ± 352 | 2692 ± 232 | 1990 ± 129 | |||
L/D | 147 | 141 | 154 | 122 | |||
ζ-potential (mV) | |||||||
Fine | Water |  − 16.5 ± 3.8 |  − 36.5 ± 3.2 |  − 36.7 ± 1.0 | 10.6 ± 0.2 | Water:  − 13.5 ± 1.6 | |
LHC-9 |  − 7.2 ± 0.6 |  − 1.8 ± 0.1 |  − 14.2 ± 1.3 | 3.3 ± 0.5 | |||
Medium | Water |  − 22.2 ± 2.1 |  − 41.5 ± 2.7 |  − 37.7 ± 1.6 | 31.6 ± 0.8 | LHC-9:  − 10.5 ± 0.6 | |
LHC-9 |  − 11.3 ± 1.1 |  − 3.9 ± 0.8 |  − 16.1 ± 1.5 | 11.5 ± 0.9 | |||
Coarse | Water |  − 20.3 ± 2.8 |  − 20.0 ± 2.5 |  − 19.9 ± 1.1 | 35.5 ± 1.0 |  | |
LHC-9 |  − 9.8 ± 0.8 |  − 2.5 ± 0.3 |  − 11.4 ± 1.0 | 12.8 ± 1.4 |