Effect of Non-Biocide Chemical and Thermal Modifications on Stability and Durability of Short Rotation Teak Wood from Plantation

Short rotation teak from plantation has been around 30 cm in diameter at the age of 15 years, however the wood is low quality especially in dimensional stability and durability. The short rotation teak wood was treated by non-biocide chemicals of Citric Acid (CA) and Benzophenone Tetracarboxylic Acid (BPTCA). The objective of this study was to improve dimensional stability and durability of the short rotation teak by modification treatment of Citric Acid and Benzophenone Tetracarboxylic Acid. Short rotation teak sapwood was impregnated by 20% and 40% of both CA and BPTCA followed by heated in oven at 150 °C (HT150 o C) for 2 h. Dimensional stability was characterized by anti-swelling efficiency (ASE), water uptake (WU), and termite durability was determined by weight loss (WL) and percentage of damage of the wood samples. The results show that the ASE values increased in the average of 46% and 50% after CA and BPTCA treatments, respectively. The WU values decreased in the average of 34% and 22% after CA and BPTCA treatments, respectively. These phenomena indicated a remarkable improvement in dimensional stability of the treated teak wood. Weight losses of treated teak woods due to termites were in the average of 1.0% and 1.5% after CA and BPTCA treatments, respectively, which categorized their durability to be class 1 (very durable). The results showed by Fourier Transform Infrared (FTIR) indicate that chemical reaction of wood lignin with CA and BPTCA chemicals was occurred. The non-biocide CA and BPTCA treatment can be applied for improving the quality of short rotation teaks for high quality wood product utilization.