A novel initiating system for wool grafting

This paper describes a new method for the grafting of methacrylic acid (MAA) and other acrylic monomers onto wool fabric in aqueous medium. The novelty principally concerns the chemical approach of the redox grafting reaction that was carried out in the presence of sodium perborate (SPB) initiator. Before the grafting reaction was started, the wool fabric was treated first with a freshly prepared ferrous ammonium sulfate (FAS) solution. The so-treated fabric formed, with SPB, an efficacious redox system capable of initiating grafting of methacrylic acid (MAA) and other acrylic monomers onto the wool fabric. The effect of the polymerization conditions on the polymer criteria, namely, graft yield (%GY), homopolymer (%HP), total conversion (%TC), and grafting efficiency (%GE), was studied. These polymer criteria were found to depend spaciously upon concentrations of the Fe2+ ion (activator), SPB (initiator), and MAA, pH of the polymerization medium, duration and temperature of polymerization. The graft copolymerization reaction has also been carried out in the presence of polymerization activators (e.g. reductant transition metal ions) and an inhibitor (e.g. hydroquinone). A suitable mechanism for the grafting processes has been suggested, in accordance with the experimental results.