5.2. Lignin Modification

The application of this approach to bamboo is schematized in Figure 10 [25].

Lignin modification in bamboo moso (a) and process of obtaining TB by epoxy infiltration (b). Reprinted with permission from [35], copyright 2022, Elsevier.

The modification of lignin was achieved by immersing the dried bamboo samples (1.5 mm thick) in an alkaline water solution containing NaOH (3.0 wt.%), Na₂SiO₃ (3.0 wt.%), MgSO₄ (0.1 wt.%), diethylenetriaminepentaacetic acid (0.1 wt.%), and H₂O₂ (4.0 wt.%), heated at 70 °C until they became completely white. The chemicals resulting from lignin modification were then removed by washing with water, followed by ethanol and acetone.