Preparation of modified sodium lignosulfonate hydrogel–silver nanocomposites

In this article, modified sodium lignosulfonate (MSLS) hydrogel particles were prepared using sodium lignosulfonate as starting material. The hydrogel particles exhibit a reversible property transformed between the two states of macrohydrogel and microhydrogel by ultrasonic dispersion and vacuum drying. Using this property, highly stable and uniformly dispersed silver nanoparticles (AgNPs) have been prepared via in situ reduction of silver ions (silver nitrate) in the microhydrogel aqueous dispersion with sodium borhydride. The hybrid microhydrogel with AgNPs was transformed into MSLS hydrogel–silver nanocomposites by drying under vacuum at 40°C. X‐ray diffraction, ultraviolet–visible (UV–vis) spectrophotometry, Fourier transform infrared spectra, atomic absorption spectroscopy, transmission electron microscopy, and scanning electron microscopy were used to characterize the composite system. The results show that the size of spherical silver nanoparticles incorporated in the hydrogel framework is about 10 nm. POLYM. COMPOS., 34:860–866, 2013. © 2013 Society of Plastics Engineers