Hydrophobic and oil-resistant coatings based on advanced green polyurethane dispersions


Correspondence to: S. Rengasamy (Email: senthilkumar_27@yahoo.com)


In recent years, there have been significant interests among scientists around the world to design smart coatings that combine the standard desirable mechanical and chemical resistance properties with additional functionalities such as oil and water repellency, hydrophobicity, self-cleaning and gas barrier properties. In the present research work, advanced aqueous polyurethane dispersion (PUD) systems have been designed and developed using three different types of polyols as soft-segments. These polyols differ in their chemical structure, functionality, polarity, and interfacial properties. The effects of soy-based polyol, hydroxy-terminated perfluoropolyether, and hydroxy-terminated polydimethylsiloxane—on various mechanical properties of their uncross-linked and cross-linked films, and more specifically on their hydrophobicity and oil-resistance (oleophobicity) have been studied. Hydrophobicity of these coatings has been characterized by their Dynamic Contact Angle measurements and their oleophobicity by n-octane absorption method. The investigations showed that presence of fluorine and siloxane structures significantly improve the hydrophobicity and oil resistance of these coatings and it is possible to optimize these properties using suitable composition of PUDs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3874–3884, 2013