Preparation And Characterization Of Polystyrene Microspheres Containing Fluorinated Dual Biocidal Groups

With the continuous improvement of people's living standards, much attention has been concentrated on health and environmental protection. To prevent harmful micro-organisms against the human body, the synthesis of efficient and safe fungicides that kill bacteria in the all media is particularly urgent. Among the many fungicides, pyridinium and N-halamine are widely studied. However, their sterilization mechanisms have a significant difference. The mechanism of pyridinium is to use its positive charge to attract bacteria with negative charge, and sterilization process does not consume pyridinium. The N-halamine has a rapid sterilization speed and consume halogen atoms in the sterilization process, but can be regenerated by the halogenation process. The pyridinium can increase the water solubility of the whole bactericidal group, while carrying positive charge can attract bacteria with negative charge, so the combination of the two kinds of sterilization groups will have synergistic effect, leading to increase the biocidal scope and efficiency.In this paper, a new kind of polyethylene microspheres containing both two N-halamine and pyridinium was designed and prepared for antibacterial tests.The monodisperse and crosslinked polystyrene microspheres were prepared by suspension polymerization method. The optimum conditions for the preparation of small particle size and uniform cross-linked polystyrene microspheres were obtained. And the sample was characterized by scanning electron microscope and optical microscope. The results showed that the microspheres were obtained.Preparation of fluorinated alkyl bromides: First, Perfluorooctyl iodide reacted with 5-ene-l-alcohol, tributyltin hydride and AIBN added to prepare 6-perfluorooctyl-l-hexanol. Then 6-perfluorooctyl-l-hexanol and carbon tetrabromide were dissolved in a mixture of anhydrous THF and anhydrous dichloromethane to obtain 6-perfluorooctyl bromide.Preparation of sterilization polymeric biocidal precursor: 4-amino pyridine reacted with allyl chloride, and the obtained organic matter was confirmed by infrared characterization.The precursor prepared in step 3, initiator azobisisobutyronitrile, and crosslinker (DVB) were added into toluene solution containing microspheres. After immersing and penetrating, then removal the solvent by filtering and placement in an oven for 1 h, the precursor and the polystyrene microspheres formed a interpenetrating network were prepared.Microspheres with polymerized precursor were quanternized by fluorinated alkyl bromide prepared in step 1, and the N-H bond of the modified microspheres was converted to N-Cl bond by the chlorination solution. Thus, microspheres containing both pyridinium and N-halamine of chloramine pyridine salts with bifunctional group were obtained on the surface.Antibacterial tests showed that sterilization microspheres containing both pyridinium and N-halamine have a strong bactericidal ability.In this paper, we have synthesized fungicides with high bactericidal ability, and the prepared microspheres have many advantages, such as: easy recovery, large specific surface area, good spherical shape, smoothness,high biocidal ability, and durable antibacterial capability.