The efficiency of the proteolytic enzyme papain in conferring shrink-resistance to wool tops and woven fabrics has been enhanced by pretreatment of the wool with lipase/sodium monoperoxyphthalate/ sodium sulphite. This process may be considered as a zero-AOX shrink-proofing treatment. The wool samples treated with this system show excellent shrink-proofed properties. Infrared spectroscopy and Xray photoelectron spectroscopy showed that the Buntë salt together with low concentrations of cystine monoxide and cystine dioxide are formed in the course of the reaction. Studies of the surface of the treated wool using scanning electron microscopy have shown the complete absence of wool scales. A mechanism is proposed for shrink resistance in the lipase/sodium monoperoxyphthalate/papain treatment.

A detailed investigation of the shrink-resist effect imparted to wool by potassium permanganate solution is described. The KMnO4 consumed by the wool increased with time, temperature, and concentration of the treating bath. The addi tion of a relatively small amount of sodium chloride in the range of 10 g/l. to the KMnO4 treatment bath incrased to some extent the KMnO4 consumed by the wool. The acidic KMnO4 treatment imparted better shrink resist properties to the wool, as well as less yellowing when compared with an alkaline treatment. The treatment produced some bleach ing effects to wool that makes it possible to use milder bleaching conditions subsequently without effecting the level of whiteness. Amino acids cystine, tyrosine, and tryptophan were greatly affected by the KMnO4 treatment. This observation may be compared with the changes associated with chlorinated or H2O2 treated wool. Nitrogen and sulfur contents decreased with increased extent of KMnO4 treatment. Alkali and urea bisulfite solubilities of the treated wool increased and were favored by increase in pH, temperature, and concentration of the KMnO4 solution. Tensile strength and elongation of the treated wool were decreased slightly by the KMnO4 treatment. The affinity of treated wool to dyeing increased, and brighter colors were imparted to dyed wool in the case of pale and medium shades as compared to untreated wool. No change in the color of the treated wool after suitable KMnO4 treat ment was observed.

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A B S T R A C TWaste wool fibers (WF) were oxidized and ball milled to enhance the exchanging ability toward some metal ions, namely copper and zinc. Wool fibers were oxidized with hydrogen peroxide and tetra acetyl ethylene diamine, followed by grinding process. Optimization of the exchanging medium with regard to the metal ion concentration, pH, and exchanging time was performed. It was observed that the ability of the wool powder (WP) and oxidized wool powder (OWP) to exchange greater amount of metal ions than the ordinary waste wool fibers. Mostly, current results verify a significant ability of the OWP to exchange copper and zinc ions from their aqueous medium. Nevertheless, the ability of all wool substrates used to exchange copper is more than their ability to exchange zinc, and as the pH of the exchanging medium increases, the uptake % of both copper and zinc ions by WF or WP increases to reach its maximum at pH 6. The efficiency of WF, WP, or OWP to adsorb copper and zinc ions after a number of adsorption/desorption tests was also studied.

ABSTRACT:Potassium permanganate-induced graftcopolymerization of methyl methacrylate(MMA) on wool fibers was investigated under a variety of conditions. The graft yield was favourably influenced by increasing the reaction time and monomer and initiator concentration. Raising the reaction temperature from 50 to 70°C causes a significant increment in the graft yield. Using 4-mmolar potassium permanganate and 6-% methyl methacrylate at pH 1 (pH was adjusted by nitric acid), a graft yield of 70% could be obtained at 70°C in two hours reaction time. This yield could be increased up to 180% if wool is treated with thioglycolic acid prior to grafting. Dinitrophenylated wool, on the other hand, showed a negligible graft yield, indicating that amino and hydroxyl groups in the wool molecules acts as sites for grafting. The consumption of permanganate was so rapid that about 60% of it was consumed in the first thirty minutes of the reaction during oxidation. On the other hand, relatively shorter time was required to cause full consumption during grafting. The excess of permanganate during grafting over that during oxidation was anticipated to initiation and termination of homopoly (methyl methacrylate). Wool with a graft yield of ca. 50% is nearly insoluble in alkali compared to the untreated one which is nearly completely soluble under similar conditions. A tentative mechanism for grafting on wool induced by permanganate was proposed.