Semi-interpenetrating polymer networks containing polysaccharides. II. Xanthan/lignin networks: a spectral and thermal characterization

Polysaccharides are important materials in food, pharmaceutical, cosmetic and related biomedical applications. Xanthan gum is a microbial polysaccharide of great commercial significance. Lignin possesses antioxidant, antimicrobial and stabilizer properties. The aim of this study was to investigate by UV-Vis and infrared spectroscopy, wide angle X-ray scattering, differential scanning calorimetry and thermogravimetric studies, the characteristics of biodegradable superabsorbant hydrogels with high swelling rate in aqueous mediums. These were obtained by crosslinking reaction between xanthan gum and different types of lignin (aspen wood lignin, annual fibre crops lignin and lignin epoxy-modified resin) using epichlorhydrine as crosslinking agent. It is expected an increased in thermal stability, hydrophilicity, biocompatibility of hydrogel-films by lignin incorporation. Applications in the food and medical field were also found.