School of Textile and Materials Engineering, Dalian Polytechnic University, 116034 Dalian, China.
ACS Appl Mater Interfaces. 2012 Jan;4(1):150-7. doi: 10.1021/am201192e. Epub 2011 Dec 13.
A multilayer photoactive coating containing surface fluorinated TiO(2) nanoparticles and hybrid matrices by sol gel approach based on renewable chitosan was applied on poly(lactic acid) (PLA) film by a step wise spin-coating method. The upper photoactive layer contains nano-sized functionalized TiO(2) particles dispersed in a siloxane based matrix. For the purpose of improving TiO(2) dispersion at the air interface coating surface, TiO(2) nanoparticles were modified by silane coupling agent 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FTS) with fluoro-organic side chains. An additional hybrid material consisting of chitosan (CS) cross-linked with 3-glycidyloxypropyl trimethoxy silane (GOTMS) was applied as interlayer between the PLA substrate and the upper photoactive coating to increase the adhesion and reciprocal affinity. The multilayer TiO(2)/CS-GOTMS coatings on PLA films showed a thickness of ~4-6 μm and resulted highly transparent. Their structure was exhaustively characterized by SEM, optical microscope, UV-vis spectroscopy and contact angle measurements. The photocatalytic activity of the multilayer coatings were investigated using methyl orange (MeO) as a target pollutant; the results showed that PLA films coated with surface fluorinated particles exhibit higher activity than films with neat particles, because of a better dispersion of TiO(2) particles. The mechanical properties of PLA and films coated with fluorinated particles, irradiated by UV light were also investigated; the results showed that the degradation of PLA substrate was markedly suppressed because of the UV adsorptive action of the multilayer coating.
采用逐步旋涂法，将含有表面氟化 TiO(2)纳米粒子和基于可再生壳聚糖的杂化基质的多层光活性涂层应用于聚乳酸 (PLA) 薄膜上。上层光活性层含有纳米级功能化 TiO(2)颗粒分散在硅氧烷基基质中。为了提高 TiO(2)在空气界面涂层表面的分散性，采用具有氟有机侧链的硅烷偶联剂 1H、1H、2H、2H-全氟辛基三乙氧基硅烷 (FTS) 对 TiO(2)纳米粒子进行了修饰。还应用了由壳聚糖 (CS) 与 3-缩水甘油氧基丙基三甲氧基硅烷 (GOTMS) 交联而成的额外杂化材料作为 PLA 基底和上层光活性涂层之间的夹层，以增加附着力和相互亲和力。多层 TiO(2)/CS-GOTMS 涂层在 PLA 薄膜上的厚度约为 4-6μm，具有高透光性。通过 SEM、光学显微镜、UV-vis 光谱和接触角测量对其结构进行了详尽的表征。通过使用甲基橙 (MeO) 作为目标污染物研究了多层涂层的光催化活性；结果表明，涂覆有表面氟化粒子的 PLA 薄膜比涂覆有纯粒子的薄膜具有更高的活性，因为 TiO(2)粒子的分散性更好。还研究了涂覆有氟化粒子的 PLA 薄膜在紫外光照射下的机械性能；结果表明，由于多层涂层的紫外吸收作用，显著抑制了 PLA 基底的降解。
