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%

STUDY ON THE MOST EFFECTIVE COMBINATION OF FLAME RETARDANT AND ANTI-AGING AGENT FOR BAMBOO MODIFICATION

In order to promote the universal application of bamboo materials as well as to provide reference for the study of the performance of bamboo, four kinds of flame retardants (boric acid (BA), borax (BX), ammonium polyphosphate (APP), disodium octaborate tetrahydrate (DOT)), two kinds of ultraviolet light absorbers (UV-531, nano TiO2) were added into waterborne polyurethane (WPU) to synthesize 5 kinds of modified coatings and coated on the surface of bamboo to make test materials. The flame-retardant analysis of the coated samples comprehensively explored the changes in flame retardancy of the test material after treatment. And the anti-aging test was carried out to investigate the color difference and adhesion change of the coating sample. The results show that the optimum flame retardant and anti-aging coating composition was obtained as 20% solid content of WPU, 8g coating amount of modifier, with the mass ratio of BA/BX/APP /DOT/water being 75:75:7:42:600, and the amount of UV-531 added being 1%

PREPARATION AND PERFORMANCE OF ANTI MILDEW GLUED LAMINATED BAMBOO

In order to strengthen the anti-mildew and anti-aging properties of bamboo when exposed outdoors, the glued laminated bamboo was impregnated with four different kinds of anti-mildew agents: tebuconazole, 3-Iodo-2-propargyl butyl carbamate (IPBC), NaBF4/didecyl dimethyl ammonium chloride (DDAC), boric acid/borax, and waterborne polyurethane coatings modified with boric acid/borax and triazole (UV1130), nano-TiO2 and nano-SiO2 were coated respectively. The modified coated glued laminated bamboo was characterized and analyzed through the experiments of wear resistance, three-point bending resistance and mildew resistance. The results showed that the glued laminated bamboo impregnated with 0.5% NaBF4/DDAC, and then coated with the waterborne polyurethane modified with boric acid/borax and nano TiO2 (the mass ratio:7.5/7.5/1.0) possessed the best mildew resistance, mechanical properties and weather resistance