The chemical graft copolymerization reactions were used to enhance water resistance of paper by reaction of acrylonitrile (AN) monomer onto cellulosic paper sheet in the presence of comonomer (styrene or acrylic acid or itaconic acid) 1 : 1 molar ratio in dimethyl formamide using benzoyl peroxide as free radical initiator under nitrogen atmosphere at 70 C. The infrared spectroscopy confirms that graft copolymerization reaction occurs onto the paper samples. Water absorption test was carried out following the Normal Protocol 7/81 (water absorption by complete immersion) to evaluate the protective effect of the graft treatment onto the paper sheet. It was found that the three graft copolymerization systems reduced the water absorption of the investigated paper and the reduction of water absorption is directly proportional to the grafting %. The wettability of the grafted and ungrafted paper sheet samples were investigated using the wicking time method which exhibits the decreasing of paper sheet wettability using the AN/S comonomers in the graft copolymerization reaction.

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The chemical graft copolymerization reaction of acrylonitrile (AN) onto paper sheet was performed. The effect of initiator concentration, monomer concentration, and temperature on the reaction rate was studied. The reaction rate equation of the graft copolymerization reaction is found to be[monomer] 1.13 . The apparent activation energy (E a ) of the copolymerization reaction is found to be 35.99 KJ/mol. The infrared characteristic absorption bands for cellulosic paper structure and the paper gr-AN are studied. Tensile break load, porosity, and burst strength were measured for the grafted and pure paper sheet. It was found that the mechanical properties are improved by grafting. The chemical resistance of the graft product against strong acid (HCl), strong alkali (NaOH), polar and nonpolar solvents was investigated. It was found that the resistance to these chemicals is enhanced by grafting. From the TGA and DTA data, it is clear that the grafted paper sheet is more thermally stable than pure paper sheet.