Preparation of an amphiphilic Janus SiO2/fluorinated polyacrylate latex film and its application as a hydrophobic fabric agent.

Amphiphilic Janus particles are characterized by their anisotropic morphology and unique physical and chemical properties. In the present research, amphiphilic Janus particles were used as stabilizing agents to prepare a fluorine-containing polyacrylate composite emulsion. The influences of the structure and dosage of amphiphilic Janus SiO2 particles and the amount of fluorine-containing monomer hexafluorobutyl methacrylate on the stability of the composite emulsion were investigated. It was noticed that when the hydrophilic and hydrophobic groups of Janus SiO2 particles were polyacrylamide and polymethyl methacrylate, respectively, the stabilization of the polyacrylate emulsion with Janus SiO2 particles was achieved. When 0.3 wt% of polyacrylamide/polymethyl methacrylate amphiphilic Janus SiO2 particles and 8 wt% of hexafluorobutyl methacrylate were used, a stable composite emulsion was obtained. The conversion rate reached 98.7% with an average particle size of 500 nm. The composite emulsion was applied for fabric finishing. The water contact angle of the fabric increased from 21.4° to 140.2°, demonstrating its greatly improved hydrophobicity. Therefore, it could be inferred that the synergistic effect of amphiphilic Janus SiO2 nanoparticles and hexafluorobutyl methacrylate improved the water resistance of the latex film.