Preparation of Fluoroalkylsilyl Polymethacrylates and Their Waterproof Application on Cotton Fabrics

Three novel fluoroalkylsilyl polymethacrylates, namely mono(fluoroalkyl)silyl polymethacrylate (PMFSA), bis(fluoroalkyl)silyl polymethacrylate (PBFSA) and tris(fluoroalkyl)silyl polymethacrylate (PTFSA), were synthesized via emulsion polymerization in this study. Subsequently, those fluoroalkylsilyl polymethacrylates were applied onto the surface of cotton fabric to make the fabric water-repellent. Particle size, zeta potential and transmission electron microscopy (TEM) were employed to analyze the emulsion stability and particle morphology. The surface properties of the coated cotton fabrics were confirmed by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Thermal properties of fluoroalkylsilyl polymethacrylates and coated cotton fabrics were evaluated by thermal gravity analysis (TGA). Contact angle measurement (CA) demonstrated that the incorporation of more fluorinated segments into the fluoroalkylsilyl methacrylate comonomer molecule and increasing fluorine content can improve the water repellency of treated cotton fabrics. In addition, the fabric's washing durability was found to be prominent. Even after 15 household machine washes, the water contact angles could be maintained as 132.7 degrees, 133.90 degrees and 128.90 degrees, respectively.