Grafting copolymerisation of vinyl monomers onto cellulose Egyptian cotton linters

Purpose - The purpose is to focus on improving the water or metal ion uptake of modified cellulose. Design/methodology/approach - Grafting copolymerisation of hydrophilic monomers such as acrylamide or hydrophobic monomers as acrylonitrile onto cotton linters was performed. Findings - The grafting process has two advantages. The first is to replace the hydroxyl group of C-6 of the glucose units in the substrate by carboxyl group that attract the metal ions from the solution. The second is to decrease the number of the hydroxyl groups in the cotton linters so that the hydrogen bonding between the cotton linters strands decreases and so the crystallinity index of substrate decreases by introduction of this hydrophilic group so it becomes more chemically active. Research limitations/implications - Partial substitution of hydroxyl groups of cellulose by more hydrophilic ones via grafting reaction followed by alkaline hydrolysis was performed. The effects of different conditions such as temperature, time, initiator concentration, monomer concentration and kind of substrate were studied. The polymerisation per cent, grafting per cent, the grafting efficiency and the nitrogen per cent of the grafted samples were determined. The molecular structures of cotton linters, grafted cotton linters with acrylamide and its hydrolysis product were studied using infrared spectroscopy, which indicates the fixation of the monomers on the cotton linters. Sodium binding capacity and the metal ion uptake of some metal ions by the product were determined. Originality/value - The water or metal ion uptake of the modified cellulose was improved.