Chemical and thermal characterizations of Pinus sylvestris and Pinus pinaster

Chemical and thermal aspects of Pinus sylvestris and Pinus pinaster were characterized, with consideration of non-extracted and cylohexane-ethanol (EtOH)-extracted woods, holocellulose, and α-cellulose. The chemical properties including cylohexane-EtOH solubility of wood were determined by standard test methods, holocellulose, α-cellulose, lignin, and ash components. Fourier transform infrared–attenuated total reflection spectroscopic (FTIR-ATR) analysis revealed changes in the chemical structure of the specimens. Lignin peaks were still observed in holocelluloses’ spectra, and substantial loss of polysaccharides were also detected. Moreover, the α-cellulose spectra of both softwoods included bands belonging to polyoses. Pinus pinaster‘s holocellulose, α-cellulose, and ash contents were higher than those of Pinus sylvestris but lignin and cylohexane-EtOH-solubility amounts were lower. The mass loss during degradation stage of Pinus sylvestris and Pinus pinaster was observed in the extracted wood respectively as 73.0 and 74.5% within the 188.7 to 422.9 °C range. The highest mass loss for Pinus sylvestris and Pinus pinaster in the carbonization step was formed in their holocelluloses respectively as 22.9 and 22.5% from 426 °C to 1017 °C.