Zhang Lianbin, Li Yang, Sun Junqi, Shen Jiacong
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, People's Republic of China.
Langmuir. 2008 Oct 7;24(19):10851-7. doi: 10.1021/la801806r. Epub 2008 Sep 4.
Complexes of poly(diallyldimethylammonium chloride) (PDDA) and sodium silicate (PDDA-silicate) are alternately deposited with poly(acrylic acid) (PAA) to fabricate PAA/PDDA-silicate multilayer films. The removal of the organic components in the PAA/PDDA-silicate mulilayer films through calcination produces highly porous silica coatings with excellent mechanical stability and good adhesion to substrates. Quartz substrates covered with such porous silica coatings exhibit both antireflection and antifogging properties because of the reduced refractive index and superhydrophilicity of the resultant films. A maximum transmittance of 99.86% in the visible spectral range is achieved for the calcinated PAA/PDDA-silicate films deposited on quartz substrates. The wavelengths of maximum transmittance could be well tailored by simply changing the deposition cycles of multilayer films. The usage of PDDA-silicate complexes allows for the introduction of high porosity to the resultant silica coatings, which favors the fabrication of antireflection and antifogging coatings with enhanced performance. Meanwhile, PDDA-silicate complexes enable rapid fabrication of thick porous silica coatings after calcination because of the large dimensions of the complexes in solution. The easy availability of the materials and simplicity of this method for film fabrication might make the mechanically stable multifunctional antireflection and antifogging coatings potentially useful in a variety of applications.
将聚二烯丙基二甲基氯化铵（PDDA）与硅酸钠的复合物（PDDA-硅酸盐）与聚丙烯酸（PAA）交替沉积，以制备PAA/PDDA-硅酸盐多层膜。通过煅烧去除PAA/PDDA-硅酸盐多层膜中的有机成分，可得到具有优异机械稳定性且与基材附着力良好的高度多孔二氧化硅涂层。覆盖有这种多孔二氧化硅涂层的石英基材由于所得薄膜的折射率降低和超亲水性而兼具抗反射和防雾性能。沉积在石英基材上的煅烧PAA/PDDA-硅酸盐薄膜在可见光谱范围内的最大透过率达到99.86%。只需改变多层膜的沉积周期，就能很好地调整最大透过率的波长。使用PDDA-硅酸盐复合物可使所得二氧化硅涂层具有高孔隙率，这有利于制备性能增强的抗反射和防雾涂层。同时，由于溶液中复合物尺寸较大，PDDA-硅酸盐复合物在煅烧后能够快速制备出厚的多孔二氧化硅涂层。材料易于获取以及这种薄膜制备方法的简单性可能使机械稳定的多功能抗反射和防雾涂层在各种应用中具有潜在用途。
