Preparation and performance of waterborne UV‐curable polyurethane containing long fluorinated side chains

Abstract

ABSTRACT Novel waterborne UV‐curable polyurethane containing long fluorinated side chains (WUVFPU) was prepared and the fluorinated component was incorporated by two novel fluorinated macromolecular diols (FDO) with different chain length as chain extender. FDO was synthesized via free radical polymerization of hexafluorobutyl methacrylate (HFBMA) using 1‐thioglycerol (TG) as chain transfer agent. Extremely low dosage of FDO incorporated could change the surface property significantly. The influence of both the content and chain length of FDO on the surface energy, surface composition and morphology were investigated by contact angle measurement, XPS and AFM. Surface energy significantly decreased at extremely low concentration of FDO. The hydrophobicity was enhanced with increasing both the content and the chain length of FDO. XPS and AFM results revealed the enhancing hydrophobicity was attributed to the enrichment of F atoms and rougher surface morphology. Gel content, pencil hardness, adhesion, and optical transmittance tests were employed to investigate the coating properties of the UV‐cured films. The preparation and investigation of WUVFPU might provide better understanding of the influence of fluorinated chain length on the properties of polyurethane for theory. Moreover, it might provide a facile and effective route to prepare polyurethane materials with low surface energy for engineering and industry. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44506.