The Development of Hydrophobic and Oleophobic Properties on Glass Surfaces by Sol-gel Process

Due to its chemistry, oxide glass surfaces are readily wetted by water (hydrophilic) making it subject to staining and corrosion. It is, therefore, highly desirable to produce a hydrophobic (water repellent) and oleophobic (oil repellent) glass surface without affecting its other properties. The subject of this doctoral work is to investigate the formation of a hydrophobic and oleophobic glass surface by a coating, that is transparent, abrasion resistant, and durable. Hydrophobic and oleophobic surfaces are normally produced by alkyl or fluoroalkyl groups connected to various molecular structures in coatings. Inclusion of these groups into a coating generally introduces structural softness and reduces transparency due to their tendency to selfassemble into separate phases. The challenge therefore, to combine hydrophobicity with optical transparency and physical hardness in a coating that strongly bonds to the glass surface. In this investigation, various methods were tried to combine these three fundamental material properties in a single glass coating that is commercially viable. In this study, a solgel system that would give a hard and transparent film on glass was formulated. Eventually, the investigation led to the development of a glass coating in the FS-Silane and FS-GPTS-Silane systems that were strongly hydrophobic, transparent, and had superior abrasion resistance than the glasses commercially available in the market today as indicated by various tests (Abrasion, Boiling water, Sunlight, Humidity and Acidic environment resistance tests). In this study, the abrasion resistance of hydrophobic and oleofobic coatings are investigated in detail for the first time. Moreover, the comprehensive comparison of prepared coatings with commercial hydrophobic coatings through intensive testing renders the doctoral thesis important with regards to the industrial applicability of the findings.