Robust Hydrophobic Coatings Using Polymer Blends for the Surface Protection of Marble

The use of marble in construction is limited by its susceptibility to water spill and weathering. Here, a series of poly (2,2,2-trifluoroethyl methacrylate) (PTFEMA) and poly (methacrylic acid) (PMAA) blend films have been coated on a marble surface to test their water spill and weathering protection capability. The morphologies of the coated polymer films on marble (i.e. surface defects and roughness) were investigated using atomic force microscopy (AFM). The hydrophobicity, adhesion strength and wear resistance of the coated films on marble were evaluated using water contact angle measurement, peel test and nanoindentation, respectively. An optimal combination of characteristics was seen when blending small amounts of PMAA (5% < x < 20 %) with PTFEMA. For these blends, the adhesion to marble and wear resistance of the coated films increased strongly over a pure PTFEMA coating, while maintaining a beneficial high water contact angle.