| The bamboo resources are very abundant in China, which application and products widespread increasingly, but how to protect the bamboo and bamboo products being a hot and difficult problem. Focus on that bamboo is liable to change color by light that could produce color groups for lignin in UV radiation. Also bamboo is especially easy to attack by bacterial and mildew for that it contains abundant nutritive materials, such as amylum, protein and fat. In this work, the most important economic bamboo species Mosco (Phyllostachys pubescens) was material, ZnO and TiO2 films with nano structures were formed in situ on the surface of bamboo via a low temperature aqueous solution route and Sel-Gel process. The effect of immersion time in seed solution, consistency of growth solution, growth time and pH of seed solution on morphologies were discussed systematically. The protective performances of films with different morphologies for bamboo were mainly investigated. And moreover, the possibility of forming nano TiO2 film on the surface of bamboo to improve its protective performances was discussed.1.Nano ZnO films formed on bamboo consisted of particle, reticulum, reticulate spHere, line, dumbbell, cylinder and hexahedron via a low temperature aqueous solution route. The route is a two-step process consisting of ZnO crystal seed formation and seed growth. The perfection degree of ZnO crystal from high to low were hexahedron, cylinder, dumbbell, reticulum, line, reticulate spHere, particle.2. Under the premise that any other conditions were consistent, the morpHologies of ZnO films tured from low perfection degree to high with immersed time in seed solution increasing. With the concentration of growth solution increased came the diameter of lines, cylinders, hexahedrons and density of reticulate structure increasing. The thickness of films, density of reticulate structure and the line's quantity, length, diameter were increased with growth time. When pH of seed solution was increasing, films were becoming reticulate structure, lines and hexahedrons easily.3. The improvement degree of anti-light discoloration, mildew proof and antibacterial performances was closely correlated to the morphologies of ZnO. The anti-light discoloration property of ZnO modified bamboo samples mainly covered with lines, reticulum, dumbbells, cylinders or hexahedrons were significantly improved. But the enhancement effect of nano particles or reticulate spheres modified samples were not significant.The mildew proof performances of bamboo mainly coverd with nano lines or reticulum were markedly enhanced, but with dumbells, cylinders or hexahedrons were poor. The bamboo mainly coverd with reticulate spHeres had perfect mildew proof performance in short time. And particle film had scarcely any mildew proof performance.The antibacterial rate of bamboo samples covered with reticulum or reticulate spheres for Escherichia coli arrived at above 99% which antibacterial properties were greatly improved. Compared with reticulate sphere film, the antibacterial activity value of reticulate one was increased, which had better antibacterial property.4. The uniform and continuous amorphous titanium dioxide thin film could form on the surface of bamboo via a low temperature sel-gel process. The film consisted of particles with the diameter of 200-300nm, which had perfect distribution. The total color difference (â–³E) of the control sample was sixteen times of the TiO2 modified one after 120h acceleration weathering, which confirmed the anti-light discoloration property of modified bamboo was greatly improved, and of which the mildewproof property was promoted by a small margin.
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