Kinetic models of swelling and thermal stability of silver/poly(vinyl alcohol)/chitosan/graphene hydrogels

Publication date: Available online 18 April 2019Source: Journal of Industrial and Engineering ChemistryAuthor(s): Katarina Nešović, Ana Janković, Aleksandra Perić-Grujić, Maja Vukašinović-Sekulić, Tamara Radetić, Ljiljana Živković, Soo-Jin Park, Kyong Yop Rhee, Vesna Mišković-StankovićAbstractSilver nanoparticles (AgNPs) were synthesized by in situ electrochemical reduction of Ag+ ions in poly(vinyl alcohol)/chitosan/graphene (PVA/CHI/Gr) hydrogel matrices with different concentrations of chitosan. The physicochemical properties of nanocomposite hydrogels were investigated by ultraviolet-visible spectroscopy (UV-vis), dynamic light scattering (DLS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM) and Fourier-transform infrared spectroscopy (FT-IR), thermal characteristics were determined by differential scanning calorimetry (DSC) and mechanical properties were measured by tensile test. The swelling studies were carried out in phosphate buffer to simulate natural physiological environment and data were fitted by several kinetic models to determine the diffusion mechanism and diffusion coefficients of the swelling medium through the hydrogel matrices. It was shown that the presence of silver nanoparticles increased the uptake capability and equilibrium swelling degree of the composite hydrogels. The antibacterial activity was confirmed against Escherichia coli and Staphylococcus a...
Source: Journal of Industrial and Engineering Chemistry - Category: Chemistry Source Type: research