{
    "protocol": "A self-healing antifogging coating based on polyzwitterion copolymer reinforced by silica nanoparticles is prepared in a one-pot synthesis. The interactions among the polymer components and silica nanoparticles can be tuned by varying the co-monomer ratio, which helps produce a coating that maintains transparency, resists scratching and abrasion, and repairs damages quickly.To synthesize hydrophilic polymers with functional groups, silica nanoparticles were first modified by dissolving 5.0 g (24 mmol) of DMASi and 3.0 g (25 mmol) of 1,3-propane sultone in 25 mL of anhydrous acetone under nitrogen, stirring for 6 h, collecting the white precipitate, and drying at room temperature. Then, 50 mg of silica nanoparticles were sonicated in 5 mL of water for 30 min, after which 9.5 mg of SBS were added, and the mixture was stirred for 6 h at 80 °C. The mixture was centrifuged at 5000 rpm for 30 min, and the centrifugate was washed three times with deionized water, dried at 80 °C, and stored under vacuum. For the fabrication of the P(SBMA7-co-HEMA3) coating, the substrates were cleaned with boiling piranha solution for 1 h, rinsed with water, and dried under nitrogen. Freshly cleaned substrates were immersed in an MPSi solution in anhydrous toluene (1:60, v/v) at 80 °C for 2 h, rinsed with toluene, and dried with nitrogen. Silica nanoparticles (2.5 or 5.0 wt% relative to the total mass of SBMA and HEMA) were sonicated in 2.5 mL of water for 20 min, a mixture of SBMA/HEMA (7/3 mole ratio), ammonium persulfate (1.0 mol%), and sodium metasulfite (0.5 mol%) was added, and the solution was stirred at 25 °C for 20 min. This solution was then spin-cast on the pretreated substrate and heated at 80 °C for 2 h to complete the polymerization and bonding."
}