Physical, durability and chemical characterization of <i>Zgmelina arborea</i> (roxb.) wood treated with lactic acid

Abstract

Chemical modification was employed to treat Gmelina arborea wood using lactic acid for property enhancement. The treated wood  samples were obtained from two different ages of 15 and 10 years and sawn into (20 x 20 x 60) mm and (20 x 20 x 20) mm for physical,  durability and chemical characterization respectively. The impregnated samples were cured for a complete modification process in the  oven at a temperature of 140^oC at varying durations (3, 6, and 9 hours). The chemical characterization was done using Fourier-infrared  spectroscopy (FTIR). The results revealed that wood aged 10 and 15 years recorded density values of 421.83 kg/m³ and 469.24 kg/m³ and  had an average value of moisture content, volumetric shrinkage, volumetric swelling, and weight loss due to leaching of 57.32% and  48.39%, 9.32% and 12.52%, 8.50% and 9.97%, and 0.21% and 0.89% respectively. The durability properties of the treated wood showed a  reduction in the leaching rate after continuous soaking in water coupled with an increase in the anti-swelling efficiency. The FTIR results  revealed that treated wood bands were within 2938 and 2842 cm⁻¹ assigned to CH stretching in aromatic methoxyl groups, and methyl  and methylene groups of side chains. The modified wood can be used where considerable dimensional stability is required for structural  use.