Properties of laminated board from Belangke bamboo (Gigantochloa pruriens) modified with citric acid, boric acid, and polystyrene

Abstract

ABSTRACT The development of bamboo as a raw material for construction materials has drawbacks, including low physical properties. Therefore, this work aimed to determine the physical and mechanical properties of laminated boards modified with citric acid, boric acid, and polystyrene. In addition, the study analysed the optimum immersion time and the phenomenon of the modifications provided. Two-step conditions were designed for the immersion of bamboo lamina. The first steps were prepared at different variation times (6, 12, and 24 h). The effect of variation time was evaluated to obtain the optimum duration treatment of bamboo lamina. Then, another step of bamboo lamina was immersion for different solutions (citric acid, boric acid, and polystyrene) at an immersion time of 6 h. The bamboo lamina was assembled into laminated boards (3 layers) measuring 30 cm × 15 cm × 1.5 cm (length × width × thickness) using isocyanate adhesive with adhesive spread level of 280 g/m2 using the double adhesive spread technique. The physical and mechanical properties of the laminated board were tested according to the JAS 234:2003 standard. The laminated board modified with polystyrene has higher density, lower delamination, higher shear strength, and higher modulus of elasticity (MOE) and modulus of rupture (MOR) than that modified with citric acid and boric acid. In addition, the bamboo laminated with 6 h and polystyrene immersion has density, moisture content, delamination, MOE, and MOR that meet the JAS 234:2003 standard. These phenomena are due to changes in the functional group and crystallinity of bamboo laminated after immersion.