Figure 6.

FT-IR spectra of the composite samples filled with cellulose fibers modified via a non-solvent approach (2000–400 cm⁻¹). Characteristic absorption bands: C–H bending vibrations (1463 cm⁻¹), C–O, C=O, C=C, –C–O–C– bonds (1300–1100 cm⁻¹), CH₂ rocking mode (719 cm⁻¹).