IJSRP, Volume 5, Issue 5, May 2015 Edition [ISSN 2250-3153]
Jignesh H. Trivedi, Wu Min, Young Huang and Harikrishna C. Trivedi
Polyacrylonitrile (PAN) grafted sodium salt of partially carboxymethylated psyllium (Na-PCMPSy-g-PAN, %G = 219.62 and %GE = 99.85) was prepared using the established optimized reaction conditions in the case of ultraviolet-radiation induced grafting of acrylonitrile (AN) onto Na-PCMPSy ( = 0.13) using uranyl nitrate (UN) as a photo-initiator. The saponification of the graft copolymer, Na-PCMPSy-g-PAN (%G = 219.62), was then performed in 0.7N NaOH solution at 90-95oC to yield a superabsorbent hydrogel, H-Na-PCMPSy-g-PAN. The swelling behaviour of the hydrogel was studied by carrying out its absorbency measurements in low conductivity water, 0.15M salt (NaCl, CaCl2, AlCl3) solutions and simulated urine (SU) at different timings. The average salt sensitivity values of the superabsorbent hydrogel were also calculated and compared. The tendency of the absorbency for the hydrogel in salt solutions is found to be in the order Na+ > Ca2+ > Al3+ for NaCl, CaCl2 and AlCl3 aqueous salt solutions. The swelling kinetics of the hydrogel in different swelling media was found to obey second order kinetics. The values of the various swelling characteristics of the hydrogel were also reported. FTIR, TGA and SEM techniques were used to characterize the products.