THE EFFECTS OF INTERFACIAL MODIFICATIONS ON THE PROPERTIES OF BAMBOO FIBER /WASTE TETRA PAK /PLA COMPOSITES

In this study, BF/TP/PLA ternary composite was constructed utilizing bamboo fiber (BF) as the reinforcing phase and waste Tetra Pak (TP) along with polylactic acid (PLA) as the matrix. The effects of different interfacial modification methods on the properties of the composites were systematically investigated. Bamboo fibers were modified using a silane coupling agent (KH570), nano-SiO2, and compatibilizers (MAH-g-PLA, MAH-g-PE). The composites were subsequently fabricated via hot pressing, and their mechanical properties, water absorption, chemical structure, and micromorphology were characterized. The results showed that after KH570 treatment, the flexural modulus and flexural strength of the composites increased by 15% and 32%, respectively. Following the introduction of compatibilizers, the water absorption was further reduced, and the thickness swelling rate was significantly improved. Optimal comprehensive performance was achieved at a nano-SiO2 content of 1 wt%; the flexural modulus reached 2524.1 MPa, exceeding the requirement of Chinese standard LY/T 3275-2021 for outdoor wood-plastic composites (≥2500 MPa), while the water absorption decreased to its lowest value (11.3%). Furthermore, interfacial bonding became more compact.