Silver nanoparticle–chitosan complexes and properties of their composites

Abstract

The dimensional characteristics of silver nanoparticles (NPs), chitosan macromolecules, and silver nanoparticle–chitosan complexes as a function of the polymer molecular weight and pH of the solution has been established. Silver nanoparticles are formed by the UV reduction of silver ions from the silver nitrate doping agent in the polymer-stabilizer solution. Dynamic light scattering studies indicate that the size of chitosan macromolecules decreases 2–4 times when its adsorption on nanoparticles takes place. Silver nanoparticles strongly affect the relaxation transition temperature of chitosan in the composite and its physicomechanical properties. It is found that the introduction of small amounts of nanoparticles decreases the T_g value by 20°C. The tensile strength of films is increased on average by ~12%, while the deformation properties remain almost unchanged.