Preparation Of Hollow Microspheres And Their Superhydrophobic And Antimicrobial Property

Bacterial adhesion on the material surface is the key factor of antibacterial ability. Therefore, the most important strategy against bacterium is to construct an antibacterial coating. Superhydrophobic surface can inhibit bacterial adhesion but does not have anti-bacterial effect. Nano-silver is characterized by broad antibacterial spectrum, good thermostability and biosafety. But the silver-coating prepared by conventional method suffers from the weakness such as fast release and antibacterial activity in a very short period.(1)Using concentrated sulfuric acid as sulfonating agent, by varying the amount of concentrated sulfuric acid and the reaction time, we discussed sulfonated polystyrene microspheres morphology. If the amount of the concentrated sulfuric acid is less or more, we can not get good morphology sulfonated polystyrene microspheres. Only using the right amount we will get a better shape sulfonated polystyrene microspheres. But for the degree of sulfonated polystyrene, when the volume of concentrated sulfuric acid is gradually increased, the sulfonated level of ulfonated polystyrene will increase. The reaction time also influenced the shape of sulfonated polystyrene. If the reaction time is too short, it can cause sulfonated polystyrene adhesions and reunion. If the reaction time is too long, it will cause sulfonated polystyrene deformation.(2)Monodisperse polystyrene (PS) spheres, which are used as templates for the synthesis of core-shell nanocomposite spheres, are sulfonated first. Then, Ag+ ions are adsorbed onto the surface of the PS template spheres via electrostatic attraction between -SO3H groups (grafted on the surface of the PS template spheres) and Ag+ ions. Ag+ ions are then reduced by and simultaneously protected by sodium citrate. In this way, the PS/Ag nanocomposite spheres in aqueous media are obtained through a so-called one-pot method. Neither additional reducing agents nor toxic organic solvents are utilized during the synthesis process. Furthermore, the coverage degree and the particle size of Ag nanoparticles on PS/Ag nanocomposite spheres is easily tuned by changing the concentration of Ag+ ions in aqueous media.(3) Polystyrene/silver/silica composite particles were coated. And we proved polystyrene/silver/silica composite particles exist within nano silver so that it has some antibacterial properties.(4) Polystyrene/silver/silica composite particles were modified so it has both anti-bacterial properties and superhydrophobic properties. Since superhydrophobic surface can reduce bacterial adhesion, the modified polystyrene/silver/silica composite particles antibacterial is further enhanced.(5)We measured the number of bacteria of polystyrene/silica composite particles and hydrophobic-modified polystyrene/silica composite particles. It found that the hydrophobic-modified polystyrene/silica composite particles antibacterial properties is better than polystyrene/silica composite particles.