Characterization of Water Hyacinth Cellulose-g-poly (Ammonium Acrylate-co-acrylic Acid)/nano-hydroxyapatite Polymer Hydrogel Composite for Potential Agricultural Application

Abstract

Polymer nano-composite was prepared by grafting partially neutralized acrylic acid onto swollen cellulose iso-lated from water hyacinth in the presence of nano-hydroxyapatite (nano-HA) usingN,N-methylene-bis-acrylamide (MBA) as the cross-linker and ammonium persulphate (APS) as the free radical initiator. Water ab-sorption tests showed an increase in swelling ratio of the copolymer with increased nano-HA content to valueof 120 g/g at 2.5%w/vabove which it declined. FTIR spectrum of nano-composite revealed grafting of the mono-mer (acrylic acid/ammonium acrylate) onto cellulose and nano-HA. Transmission electron microscopy (TEM)images of nano-HA synthesized in the presence of Triton X-100 (non-ionic surfactant) displayed rod-shaped ag-glomerates and nano-particle dispersion within the copolymer matrix. Energy dispersive X-ray (EDX) spectra re-vealed the constituents of nano-composite to be mainly C, O, Ca and P, while N was not detected by this method.X-ray diffractograms (XRD) of cellulose grafted copolymer showed a more amorphous structure relative to thatof dry water hyacinth cellulose and also presence of crystalline nano-HA within the copolymer. This polymernano-composite could be beneficial in agriculture in aiding moisture retention as well as a source of P which oc-curs through microbial degradation of cellulose grafted copolymer and solubilization of nano-HA