Synthesis and characterization of chitosan modified polyurethane bio-nanocomposites with biomedical potential

A series of chitosan (CS) and montmorillonite (MMT) clay based polyurethane bio-nanocomposites were synthesized by step growth polymerization; reacting hydroxyl terminated polybutadiene (HTPB) and toluene diisocyanate (TDI) to improve thermal and antibacterial properties of polyurethane (PU). Five different PU samples were prepared by varying mole ratio of CS and 1,4-butane diol (from 0 to 2 mol). Structural studies of PUs through FTIR and 1H NMR spectroscopy confirmed the incorporation of CS into the polymer matrix. The scanning electron microscope (SEM) analysis confirmed well dispersion of MMT clay into the PU matrix. Thermogravimetric analysis (TGA) of PUs indicated significant enhancement of thermal stability of PU with addition of CS. Antibacterial properties of PUs were measured by disc diffusion method; showed excellent potential against the selected strains. On the whole, CS showed potential to improve the antibacterial and structural properties of PU significantly; which might be precursor for biological applications.