Evaluation of anti-mold, termite resistance and physical-mechanical properties of bamboo cross-linking modified by polycarboxylic acids

Bamboo strips can be made into large-scale bamboo-based materials for construction and engineering materials, but the susceptibility of bamboo to degradation associated with moisture and microorganism attack greatly restricts its applications. In this study, chemical cross-linking modification using polycarboxylic acids [citric acid (CA) and 1,2,3,4-butanetetracarboxylic acid (BTCA)] was employed to modify the performance of bamboo strips. The results confirm the esterification reaction between CA/BTCA and bamboo components. The anti-mold property of bamboo is notably improved and achieves rating 1 mold coverings (<25%). Treated samples show high termite mortality and low mass losses, indicating good termite resistance. Owing to the cross-linking modification, the dimensional stability of bamboo is improved with anti-swelling efficiency of 29% for CA treatment and 31% for BTCA treatment. Compared with the untreated sample, polycarboxylic acids treatments cause 20-30% reduction in modulus of rupture, slight increase in modulus of elasticity, and 17-20% increase in compression strength. Moreover, the thermal stability of bamboo is enhanced by cross-linking modification. Polycarboxylic acids treatment is an eco-friendly, low-cost, and versatile method to improve bamboo properties. (C) 2020 Elsevier Ltd. All rights reserved.