Fabrication of super-hydrophobic surfaces for enhanced stone protection
Fabrication of super-hydrophobic surfaces for enhanced stone protection
复制标题
DOI：
10.1016/j.surfcoat.2008.10.041
复制
发表时间：
2009-02-25
影响因子：
5.4
通讯作者：
Panayiotou, C.
中科院分区：
文献类型：
--
作者：
Manoudis, P. N.;Tsakalof, A.;Panayiotou, C.
在目前的研究中，我们证明了通过添加二氧化硅纳米颗粒对商业硅氧烷保护组合物的改性大大提高了其保护效率，并使处理后的石材表面具有超疏水性和自清洁性。表面疏水化的程度取决于纳米颗粒浓度，并且对于用改性组合物处理的白色希腊大理石（Naxos、Pentelic和Thassos）的情况，在1%w/v的纳米颗粒下达到类似于160度的最大值。通过扫描电子显微镜（SEM）对表面形态的研究揭示了由硅氧烷聚合物固结的纳米颗粒聚集体形成的微米级突起（直径为10-100 μ m）的存在。突起的直径和表面密度取决于纳米颗粒浓度。通过原子力显微镜（AFM）观察突起的发展的纳米结构。二氧化硅颗粒的纳米尺寸对于处理过的大理石表面的超疏水化至关重要。在与硅氧烷混合的微米级二氧化硅颗粒并相应地施加在类似的白色希腊大理石上的情况下，没有实现超疏水效果，并且观察到的水接触角显著更低。在疏水性不是最佳石头和石碑保护的唯一参数的情况下，其他重要参数，例如水蒸气渗透性，还研究了水毛细吸收和石头颜色改变，并建立了它们对纳米颗粒浓度的依赖性。(c)2008 Elsevier B. V.保留所有权利。
In the current study, we demonstrate that the modification of a commercial siloxane protective composition by the addition of silica nanoparticles substantially enhances its protective efficiency and renders the treated stone surface super-hydrophobic and self-cleaning. The extent of surface hydrophobization depends on nanoparticle concentration and reaches a maximum value of similar to 160 degrees at 1% w/v of nanoparticles for the case of white Greek marbles (Naxos, Pentelic and Thassos) treated with the modified composition. The investigation of the surface morphology by scanning electron microscopy (SEM) reveals the presence of micron-sized protrusions (10-100 mu m in diameter) formed by nanoparticle aggregates consolidated by the siloxane polymer. The diameter and surface density of the protrusions depend on nanoparticle concentration. The developed nanostructure of the protrusions was observed by atomic force microscopy (AFM). The nano-dimensions of the silica particles are essential for the superhydrophobization of the treated marble surfaces. In the case of micron-sized silica particles that were mixed with siloxane and were applied accordingly on similar white Greek marbles, the superhydrophobic effect was not achieved and the observed water contact angles were substantially lower.In the event that hydrophobicity is not the sole parameter of optimal stone and stone-monuments protection, other important parameters, such as water vapor permeability, water capillary absorption and stone color alterations, were also investigated and their dependence on nanoparticle concentration was established. (c) 2008 Elsevier B.V. All rights reserved.