Superabsorbent nanocomposite from sugarcane bagasse, chitin and clay: Synthesis, characterization and swelling behaviour

A nanocomposite comprising crosslinked hybrid polymer network was prepared using chitin and sugarcane bagasse in presence of montmorillonite clay. Chitin and sugarcane bagasse were micro-fibrillated by ultrasonication of their suspension in an ionic liquid 2-hydroxy ethylammonium formate. Optimum reaction conditions were established by variation of amounts of initiator, monomer and crosslinker, and microwave irradiation to obtain nanocomposite with swelling degree above 1000% in 24 h. Slow and steady swelling was observed and the sample swelled to about 15,000% to form a hydrogel in 15 days. The nanocomposite was characterized by swelling degree, infrared spectroscopy, X-ray diffraction and scanning electron microscopy. Swelling and reswelling in water was studied for four cycles, erosion was highest after first cycle but became negligible for consecutive cycles. The swelling degree increased up to three cycles then became constant. Nanocomposite shows sufficient antimicrobial activity against S. aureus and E. coli. It is biodegradable in moist garden soil in three months.