Synthesis,Characterization, and Microbial Activity of Nanocomposites of Chitosan-Graft-Poly(4-vinyl pyridine) Copolymer/Organophilic Montmorillonite

Organophilic montmorillonite was synthesized by cationic exchange between Na⁺-MMT and N-octyl-N-vinyl-2-pyrrolidonium bromide. Nanocomposites of chitosan grafted with 4-vinyl pyridine and organophilic montmorillonite were prepared in acetic acid using ammonium persulfate as initiator. The molecular structure of the grafted copolymer was confirmed by FTIR. The degree of dispersion and the intercalation spacing of these nanocomposites were investigated using X-ray diffraction. The enhanced thermal stability of nanocomposites was verified by differential scanning calorimetry and thermogravimetric analysis. Preliminary results of the antibacterial and antifungal activities of the prepared nanocomposites have demonstrated significant antimicrobial activity of the nanocomposites compared with pure and grafted chitosan.