The graft copolymerization of acrylonitrile (AN) onto cassava starch (CS) with sodium bisulphite and potassium persulphate (KPS) as initiators was prepared. AN was grafted with gelatinized cassava at 70°C via redox method. The monomer ratios and reaction temperature were varied to obtain the maximum grafting efficiency and high grafted yield. The maximum grafting efficiency (91%) and grafted yield (93%) were attained at 50°C with ratio AN:CS 3:1 in 3 h. Poly(AN-grafted (g)-CS) was then modified with hydroxylamine hydrochloride (NH2OH.HCl) to convert the nitrile group into absorbing characteristic properties. The poly(AN-g-CS) and amidoxime-modified poly(AN-g-CS) were characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy, thermal gravimetric analysis (TGA) and Brauner-Emmet-Teller. The IR spectra proved that the grafting of AN onto CS was successful and the poly(AN-g-CS) was successfully modified with NH2OH.HCl. It was shown that the specific surface area, pore volume and average pore diameter of CS were increased from 54.75 m2.g–1, 245.39 m2.g–1,0.336cm3.g–1 to 0.843 cm3.g–1 and 3.95 nm to 13.02 nm, respectively. TGA analysis proved that poly(AN-g-CS) and amidoxime-modified poly(AN-g-CS) are thermally more stable compared to CS.
Key words: Cassava starch; acrylonitrile; graft copolymerization; chemical modification; hydroxylamine hydrochloride
El-Tahlawy, K., Vanditti, R.A. and Pawlak, J.J. (2007) Aspects of the preparation of starch microcellular foam particles crosslinked with glutaraldehyde using a solvent exchange technique, Carbohydrate Polymers, 67 (3), 319–331.
Lapasin, R.S. (1995) Rheology of industrial polysaccharides: in Theory and Application New York, Aspen Publishers, Journal of Colloids and Food Hydrocolloids, 10, 1016.
Pillai, C., Paul, W. and Sharma, C.P. (2009) Chitin and chitosan polymers: Chemistry, solubility and fibre formation, Journal of Progress Polymer Science, 34 (7), 887–913.
Bastos, D.C., Santos, A.E.F., Silva, M.L.V., da Fonseca, M.D. and Simao, R.A. (2013) Inducing surface hybridazition on cornstarch film by SF6 and HMDSO plasma treatment, Journal of carbohydrate polymers, 91 (2), 675–681.
Haag, A.P. (2006) Mechanical properties of bacterial exopolymeric adhesives and their commercial development, in Biological Adhesives, Springer Berlin Heidelberg.
Shi, R., Zhang, Z.Q., Han, Y., Zhang, L., Chen, D. and Tian, W. (2007) Journal of Carbohydrate Polymers, 69, 748.
Reis, A.V., Guilherme, M.R., Cavalcanti, O.A., Rubira, A.F. and Muniz, E.C. (2007) Superabsorbent hydrogel composed of covalently crossedlinked gum Arabic with fast swelling dynamics, Journal of Polymer Science, 47, 2023.
Dworjanyn, P.A., Fields, B. and Garnett, J.L. (1989) Effects of various additives on accelerated grafting and curing reactions initiated by UV and ionizing radiation, Journal of Radiation Physics and Chemistry, 381, 112–131.
Khan, F. (2004) Photo induced graft-copolymer synthesis and characterization of methacrylic acid onto natural biodegradable lignocellulose fibrer, Journal of Biomacromolecules, 5, 1078–1088.
Kaewta, K. and Varaporn, T. (2008) Preparation cassava by suspension polymerization, Journal of Carbohydrate polymers, 73, 647–655.
Fang, J.M., Fowler, P.A. and Hill, C.A.S. (2005) Studies on the grafting of acrylated potato starch with styrene, Journal of Applied Polymer Science, 96, 452–459.
Mishra, V. and Kumar, R. (2011) Uptake of hazardours heavy metal ions by aqueous solution of poly(acrylamide) prepared through atom transfer radical polymerization process, Journal of Applied Polymer Science,128 (5), 3295–3307.
Bianchi, E., Bonazza, A., Marsano, E. and Russo, S. (2010) Free radical grafting onto cellulose in homogeneous conditions. 2. Modified cellulose-methyl methacrylate system, Journal of Carbohydrate Polymers, 41, 47–53.
Niu, L., Deng, S., Yu, G. and Huang, J. (2010) Efficient removal of Cu(II), Pb(II), Cr(VI) and As(V) from aqueous solution using an aminated resin prepared by surface-initiated atom transfer radical polymerization, Journal Chemical Engineering, 165, 751–757.
Horzum, N.W., Shahwan, T., Parlak, O. and Demir, M.M. (2012) Synthesis of amidoximated polyacrylonitrile fibres and its application for sorption of aqueous uranyl ions under continuous flow, Journal of Chemical Engineering, 213, 41–49.
Ingole, N.W. and Patil, V.N. (2013) Cadmium removal from aqueous solution by modified low cost adsorbent(s): A state of the art, Journal of civil, Structural, Environmental and Infrastructure Engineering Research and Development, 3 (4), 17–26.
Nair, S.B. and Jyothi, A.N. (2014) Cassava starch-graft polymethacrylamide copolymers as flocculants and textile sizing agents, Journal of Applied Polymer Science, 131 (2).
Feng, Q., Wang, X., Wei, A., Wei, Q., Hou, D.W., Liu, X. and Wang, Z. (2011) Surface modification Polyacrylonitrile nanofibres and application for metal ion chelation, Journal of Fibres and Polymers, 12, 1025–1029.
Abel-Razik, E.A. (1990) Hamogeneous graft copolymerization of acrylamide onto ethyl-cellulose, Journal of Carbohydrate Polymer. 31, 1739–1744.
Jamil, M.S.N., Khairuddin, M. and Daik, R. (2015) Preparation of acrylonitrile/acrylamide copolymer beads via redox method and their adsorption properties after modification, e-polymers, 15 (1), 45–54.
Shaaban, A.F., Fadel, D.A., Mahmoud, A.A., Elkomy, M.A. and Elbahy, S.M. (2014) Synthesis of a new chelating resin bearing amidoxime group for adsorption of Cu(II), Ni(II) and Pb(II) by bath and fixed-bed column methods, Journal of Environmental and Chemical Engineering, 2, 632–641.
Masoumi, A. and Ghemy, M. (2014) Removal of metal ions from water using nanohydrogeltraga-canth gum-g-polyamidoxime: Isotherm and kinetic study, Journal of Carbohydrate Polymers, 108, 206–215.
Bajaj, P., Sreekumar, T.V. and Sen, K. (2001) Thermal behavior of acrylonitrile copolymers having methacrylic and itaconic acid comonomers, Journal of Carbohydrate Polymers, 42, 1707.
Athawale, V.D. and Lele, V. (2000) Synthesis and characterization of graft copolymers of maize starch and methacrylonitrile, Journal of Carbohydrate Polymer, 41, 407–416.
Godshall, D., Rangarajan, P., Baird, D.G., Wilkes, G.L., Bhanu, V.A. and McGratt, J.E. (2003) Incorporation of methyl acrylate in acrylonitrile based copolymers: Effects on melting behavior, Journal of PolymerScience, 44 (15), 4221–4228
Fortuna T., Juszczak L. and Palasinski M. (1998) Change in the granule porosity on modification of starch, Journal of Zywnosc, Technologia, Jakosc, 4 (17), 124–130.