Figure 2
PNIPAM modified wood cell walls were analyzed with confocal Raman microscopy. (a,b) While in earlywood (EW) typical bands of the polymerization initiator were found at 299 cm−1, the PNIPAM assigned bands were found in EW and transitionwood (TW) at 848 cm−1. Integrating these two bands resulted in false color images revealing the functionalized areas within the wood cell wall cross-section (blue = initiator, green = PNIPAM, red = wood based on lignin band integration at 1603 cm−1) in earlywood area and transitionwood. (c) Average spectra of the identified chemically different regions in EW and TW were extracted.
