Thermal and hydrophobic properties of glycerol stearate-modified Pinus radiata wood

Abstract

Glycerol stearate was synthesized by esterification with non-toxic, inexpensive glycerol and stearic acid. The composite of glycerol stearate and Pinus radiata wood was prepared by vacuum impregnation. By Fourier transform infrared (FTIR) analysis, there was the generation of new C=O stretching vibration band of glycerol stearate in comparison with stearic acid. This confirms that glycerol stearate was successfully synthesized. The weight gain, FTIR spectrum and morphological analyses of the composite indicate that glycerol stearate was impregnated into the interior lumina of the cells. Thermal analysis showed that the maximal degradation temperature of the composite was 42 °C higher than untreated wood. Contact angle images indicated that the value of the composite was 134.2°. Hydrophobicity (the repulsion of water) of the composite was stronger than glycerol stearate, which a large number of hydroxyl of wood reacted with the oxygen-containing groups of glycerol stearate, improved hydrophobicity and thermal stability, thereby enhancing the potential application of P. radiata wood.

Keywords

Wood composite / Glycerol stearate / Pinus radiata / Hydrophobicity / Thermal stability

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