Table 2.
Physicochemical properties of solvent-extracted bamboo residues and extracted lignin fractions
| Sample | Accessibility | Hydrophobicity | Crystallinity | Bhkl | Dhkl | Zeta potential | Molecular weight (kDa) | |
|---|---|---|---|---|---|---|---|---|
| (mg/g) | (mg/mL)a and (°)b | (%) | (nm) | (nm) | (mV) | Mw | Mn | |
| DAP-BR | 218 | 0.7a | 38 | 3.03 | 0.403 | −24.3 ± 0.5 | – | |
| Dio-BR | 320 | 3.6a | 36 | 3.64 | 0.401 | −20.4 ± 0.2 | – | |
| Eth-BR | 236 | 3.1a | 39 | 3.45 | 0.402 | −22.1 ± 1.1 | – | |
| THF-BR | 251 | 3.0a | 34 | 3.99 | 0.400 | −21.5 ± 0.3 | – | |
| DAP-MWL | – | 76.4b | – | – | – | −37.0 ± 0.3 | 9.1 | 2.9 |
| Dio-MWL | – | 76.2b | – | – | – | −31.8 ± 0.2 | 10.8 | 3.6 |
| Eth-MWL | – | 73.8b | – | – | – | −34.3 ± 0.3 | 13.0 | 4.6 |
| THF-MWL | – | 75.1b | – | – | – | −37.0 ± 0.3 | 13.2 | 4.7 |
| Dio-SL | – | 69.5b | – | – | – | −32.8 ± 0.2 | 2.4 | 0.7 |
| Eth-SL | – | 68.5b | – | – | – | −29.1 ± 1.1 | 1.2 | 0.4 |
| THF-SL | – | 64.3b | – | – | – | −26.1 ± 0.1 | 2.0 | 0.4 |
| DAP-MWL | – | 76.4b | – | – | – | −37.0 ± 0.3 | 9.1 | 0.5 |
DAP-BR dilute acid-pretreated bamboo residues, Dio-BR DAP-BR extracted by 1,4-dioxane using a concentration of 96% (v/v, water/1,4-dioxane), Eth-BR DAP-BR extracted by ethanol extraction using a concentration of 95% (v/v, water/ethanol), THF-BR DAP-BR extracted by tetrahydrofuran using pure tetrahydrofuran; MWL milled wood lignin, SL surface lignin
aAnalyzed by dye absorption
bAnalyzed by water contact angle