Preparation and characterization of saponified delignified cellulose polyacrylonitrile-graft copolymer
2002
Farag, S. | Al-Afaleq, E.I.
Acrylonitrile was graft polymerized onto delignified cellulose using ceric ammonium nitrate as initiator. Polymerization typically yield cellulose-g-polyacrylonitrile containing 45.05 g acrylonitrile per 100 g sample. The resulting copolymer was saponified with (0.75 M) sodium hydroxide. The treatment was carried out at 100 degrees C for different time duration. The extent of saponification was assessed by estimating carboxyl content, nitrogen content, acrylonitrile and acrylic acid before and after saponification. The alkaline treatment results in a decrease in nitrogen content and increase in carboxyl content. Moreover, beside the conversion of cyanide groups to carboxyl groups, alkaline treatment brings about cleavage of ether linkage of the copolymer. The potential value of the saponified modified cellulose is serve as a water absorbance was assessed through measurements of critical properties such as solubility and absorbance of water, saline water and synthetic urine. Also, the property of the prepared sample of swelling to gel was used to absorb water from ethanol-water mixture.
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