Figure 3

(a) Raman spectra of the fiber and the surrounding GMA. Two characteristic modes of GMA (at 603.4 cm⁻¹ and 1725 cm⁻¹) that were not observed in the fibers are highlighted. CH₂ wagging mode (1440–1480 cm⁻¹ range) and a characteristic cellulose mode at 380.8 cm⁻¹ are also highlighted. (b) 20 × 20 µm² optical microscopy image of the fiber embedded in GMA. The dashed white line marks the fiber perimeter. The laser spot on the sample is visible and marks the spot from which the Raman spectrum (a) of the fiber was measured. For the reported GMA spectrum, the laser spot was positioned in the bottom-right of (b).