Characterization of Tunisian Aleppo pine tannins for a potential use in wood adhesive formulation

Abstract The phenolic composition of Tunisian Aleppo pine barks was studied. Colorimetric assays, Fourier transformed infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) were used to examine Aleppo pine tannins. Analyzes showed that Aleppo pine barks are rich in condensed tannins, especially in procyanidin and prodelphinidin tannins. The reactivity to formaldehyde test (Stiasny number) showed the possible use of Aleppo pine tannins in wood adhesive formulation. Thermomechanical analysis (TMA) and strength analysis of Aleppo pine tannin/hexamin based resin showed important bonding properties.