The Assesment of the Decayed Lime Wood Polymeric Components by TG and FT-IR Parameters Correlation

Abstract

The restoration and conservation practices of wooden artifacts increasingly need more nondestructive, inexpensive and no-time consuming diagnosis methods. A number of twelve samples of lime wood in various states of degradation from furniture and panel painting were investigated by thermal analysis and infrared spectroscopy. The present work was undertaken to quantify the degree of complementarity of the TG and FT-IR methods by assessing >the ration between cellulose, hemicelluloses and lignin of the decayed lime wood by the correlation of the parameters RTG = ΔmHC /ΔmL from TGA data, and R1FTIR = Aab1370/Aab1505, R2FTIR = Abz1370/Abz1505, R3 FTIR = Iab1370/Iab1505, R4FTIR = Ibz1370/Ibz1505 , from the corresponding peaks of cellulose and hemicelluloses at ~ 1370 cm-1 and of lignin at 1505 cm-1 in FT-IR spectra, where RTG is the ratio between the mass loss of cellulose & hemicelluloses ΔmHC and the mass loss of lignin ΔmL; R1FTIR, R2FTIR, are the ratio between the absolute peaks area Aab1370/Aab1505, and the normalized peaks area Abz1370/Abz1505, respectively, while R3FTIR, R4FTIR are the ratio between the absolute peaks intensity Iab1370/Iab1505, and the normalized peaks intensity Ibz1370/Ibz1505, respectively. We found that the TG parameter decreases in the same order as FT-IR parameters R1 FTIR, R2FTIR, R3FTIR, R4FTIR, and relates well in the values with R1FTIR.

Keywords

• lime wood
• decayed wood
• wood diagnosis
• infrared spectroscopy
• thermal analysis