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.

THE EFFECT OF COMPOSITE MODIFIED BORON-BASED WATERBORNE FLAME-RETARDANT COATING ON COMBUSTION PERFORMANCE OF BAMBOO DECORATIVE FILAMENT

To address the flammability of bamboo decorative filament, seven waterborne composite flame-retardant coating systems were developed using waterborne acrylic resin as the film-forming matrix, with boric acid, borax, ammonium polyphosphate (APP), nano-SiO2, and disodium octaborate tetrahydrate (DOT). The filament was treated as primer-only, topcoat-only, and combined primer/topcoat application. The combustion performance was evaluated by a cone calorimeter following ISO 5660-1: 2002. The results indicated that in the primer-only coating system, the boric acid/borax/disodium octaborate tetrahydrate composite system reduced total smoke production (TSP) by 11.90%, while the total heat release (THR) of the boric acid/borax/disodium octaborate tetrahydrate/ammonium polyphosphate composite system decreased by 18.83%. In the topcoat-only system, the boric acid/borax single-component system exhibited the optimal comprehensive performance, which the peak value of heat release rate (HRR) and the TSP decreased 13.54% and 8.24%, resp. In the combined primer-topcoat systems, THR reductions of 10.99% and 10.21% were achieved. Notably, nano-SiO2/boric acid/borax exhibited superior smoke suppression performance, with a 14.12% decrease in TSP, attributed to the synergistic physical barrier effect between the silicate network formed by nano-SiO2 and the boron-based glassy protective layer

PREPARATION PROCESS AND INTERFACE MODIFICATION ON THE MECHANICAL PROPERTIES OF BAMBOO FIBER/POLYPROPYLENE CARBONATE COMPOSITES

In this study, bamboo fiber (BF) and polypropylene carbonate (PPC) were used to prepare BF/PPC composite materials. The single factor test combined with orthogonal experiment was used to investigate the effects of different hot pressing process conditions (hot pressing temperature, hot pressing pressure and hot pressing time) on the mechanical properties of BF/PPC composites. Based on the hot pressing process results, the filler nano-calcium carbonate (Nano-CaCO3), γ-aminopropyl triethoxysilane (KH550) and maleic anhydride (MAH) were added respectively to the composites to improve the interface between BF and PPC in order to increase the mechanical properties of the composites. The results showed that the reasonable preparation conditions of BF/PPC composites with the best mechanical properties were set at 170°C, under 1.9 MPa for 10 min. Compared with PPC samples, the tensile modulus, bending modulus and impact strength of BF/PPC composites could be increased to 102%, 38.69% and 65.13%, respectively. The optimal interface modification treatments have been proved that nano-CaCO3 with 10% content could increase the tensile modulus and impact strength to 70.53% and 65.84%, while the best result for the bending modulus of BF/PPC composites was modified with MAH with 2.5% content, which could increase to 28.46%