Application of carboxymethylcellulose hydrogel based silver nanocomposites on cotton fabrics for antibacterial property.

In this study, fumaric acid (FA) crosslinked carboxymethylcellulose (CMC) hydrogel (CMCF) based silver nanocomposites were coated on cotton fabric for antibacterial property for the first time. The performance of the nanocomposite treated cotton fabric was tested for different mixing times of hydrogel solution, padding times and concentrations of silver. The cotton fabrics treated with CMC hydrogel based silver nanocomposites demonstrated 99.9% reduction for both Staphylococcus aureus (Sa) and Klebsiella pneumonia (Kp). After one cycle washing processes of treated cotton fabric, there is no significant variation observed in antibacterial activity. From SEM and AFM analyses, silver particles in nano-size, homogenously distributed, were observed. The treated samples were also evaluated by tensile strength, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) analysis, fluid absorbency properties, and whiteness index. The treatment of cotton fabric with CMCF hydrogel did not affect the whiteness considerably, but increased the absorbency values of cotton.

Preparation of pH- and ionic-strength responsive biodegradable fumaric acid crosslinked carboxymethyl cellulose.

A novel biodegradable sodium carboxymethyl cellulose (NaCMC)-based hydrogel was synthesized by using fumaric acid (FA) as a crosslinking agent at various ratios. Hydrogels (CMCF) were characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Swelling behaviors of hydrogels were investigated in distilled water, various salt, and pH solutions. The FTIR results indicated the crosslinking between carboxyl groups of FA with hydroxyl group of NaCMC through ester formation. AFM analyses showed that roughness of hydrogel surface decreased with increasing crosslinker concentration. The swelling capacity decreased with an increase in charge of the metal cation (Al(3+)

A natural sorbent, Luffa cylindrica for the removal of a model basic dye.

In this work, application of Luffa cylindrica in malachite green (MG) removal from aqueous solution was studied in a batch system. The effect of contact time, pH and temperature on removal of malachite green was also investigated. By the time pH was increased from 3 to 5, the amount of sorbed malachite green also increased. Beyond the pH value of 5, the amount of sorbed malachite green remains constant. The fits of equilibrium sorption data to Langmuir, Freundlich and Dubinin-Radushkevich equations were investigated. Langmuir isotherm exhibited best fit with the experimental data. Monolayer sorption capacity increased with the increasing of temperature. Sorption kinetic was evaluated by pseudo-first-order, pseudo-second-order, Elovich rate equations and intraparticle diffusion models. It was inferred that sorption follows pseudo-second-order kinetic model. Thermodynamic parameters for sorption process were also found out. Spontaneous and endothermic nature of sorption was obtained due to negative value of free energy (DeltaG(o)) and positive value of enthalpy (DeltaH(o)) changes. FTIR analyses were also conducted to confirm the sorption of malachite green onto L. cylindrica.