Figure 4.

FT-IR spectra of the neat ethylene-norbornene copolymer and a composite sample filled with untreated cellulose fibers (4000–400 cm⁻¹) (a) and its magnification (1800–400 cm⁻¹) (b). Characteristic absorption bands: C–H stretching (2915 cm⁻¹, 2848 cm⁻¹), C-H bending vibrations (1463 cm⁻¹), C–O, C=O, C=C, –C–O–C– bonds (1300–1100 cm⁻¹), CH₂ rocking (719 cm⁻¹).