SynopsisGraft copolymerization of hydroxyethyl methacrylate (HEMA) onto poly(ethy1ene terephthalate) (PET) fibers using benzoyl peroxide (BP) as initiator was carried out in water and in water/organic solvent as a reaction medium. The effect of initiator concentration, reaction time, temperature, and reaction medium as well as addition of FeSO,, to the polymerization medium was studied. Percent grafting was enhanced significantly by increasing BP concentration up to 0.016 mol/L and then decreased upon further increase in initiator concentration. Increasing the monomer (HEMA) concentration up to 0.48 mol/L improves significantly the graft yield. Raising the polymerization temperature up to 85°C causes a significant increase in grafting yield; further increase in temperature leads to decrease in graft yield. Incorporation of Fe+* ions in the polymerization system decrease the graft yield. The same situation is encountered when water/solvent mixture is used as reaction medium. Solvent employed were methanol, toluene, and benzene.

Synthesis, characterization, and amidoximation of diaminomaleodinitrile-functionalized polyethylene terephthalate (PET) grafts were studied. Azobisisobutyronitrile (AIBN) was used as an initiator. Optimum conditions for grafting were as follows: monomer concentrationWater uptake of the grafted-PET film increased with the increase of grafting yield. The imparted cyano group of the grafted polymer chains (with degree of grafting up to 83%) was converted into amidoxime group by reaction with hydroxylamine. The unique advantage of this polymer is that it contains double amidoxime groups per repeating unit and an additional diethylene spacer unit between neighboring amidoxime groups in each monomeric unit. The grafted-PET films were characterized by FTIR spectroscopy, differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). The grafted-PET films are more thermally stable than the ungrafted-PET membrane, since the grafted mem-brane showed a single degradation pattern despite having two components. A decrease in T g values is observed as the grafting yield of copolymers increases indicating the incorporation of polydiaminomaleodinitrile chains in amorphous copolymers with higher thermal stability. The prepared amidoximated DAMN83-g-PET was investigated for its properties in removing heavy toxic metals, such as Pb 2þ , Cd 2þ , Zn 2þ , Fe 2þ , Cu 2þ , Ni 2þ , Co 2þ , and Ag 1þ from waste water. The amidoximated-film is characterized by a considerably greater binding ability with respect to heavy metals. The nature of the metal ion also has great importance in the amount binding to the polymeric material. The kinetics of the sorption/desorption process for Co 2þ , Ni 2þ , and Zn 2þ are investigated.

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