Preparation of dimensionally stable and strong thin-type bamboo bundle laminated veneer lumber through delignification and phenolic resin synergies

Abstract

The development of thin-type bamboo bundle laminated veneer lumber (T-BLVL) represents a significant advancement in environmentally friendly and sustainable building materials. However, the application of T-BLVL is still hindered by poor dimensional stability and low mechanical strength. In this study, the delignified thin-type bamboo bundle laminated veneer lumber (D-T-BLVL) was prepared through the partial delignification of bamboo bundles and the synergistic effects of phenolic resin (PF). These effects included gluing, strengthening, and waterproofing. D-T-BLVL exhibited high strength, dimensional stability, and a remarkable thickness of only 5 mm. After the removal of 26 % lignin, the porosity of bamboo bundles increased by 117 % compared with natural bamboo bundles, facilitating enhanced PF infiltration. D-T-BLVL exhibited a bending strength of 281.84 MPa, representing an 83.75 % increase over that of T-BLVL (153.38 MPa). Additionally, the water absorption thickness expansion rate of D-T-BLVL (3.37 %) was only approximately 1/4 times that of T-BLVL (13.30 %). The development of D-T-BLVL provides valuable guidance for developing wind turbines, infrastructures, and other advanced technologies.