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Sulfonation of polyglycidyl methacrylate (PGMA) chains grafted onto nonwoven polypropylene fabric is investigated in detail. Sulfonation reaction consists in implantation of sulfonate groups via epoxy ring-opening of PGMA chains grafted onto nonwoven polypropylene fabric by reaction between the GMA-grafted sample and sodium hydrogensulfite in water-dimethylformamide solution. On the basis of analyses of IR spectra of the appropriate samples and data of backward titration, two simultaneous processes are demonstrated to take place during the sulfonation reaction. These processes are the implantation of sulfonate groups via opening of the GMA epoxy rings and hydrolysis of the GMA epoxy rings with a-glycol groups formation. The main peculiarities of the sulfonation reaction in depending on the GMA grafting degree are reported.

The ability of powdered Nylon 612 to bind methyl orange, ethyl orange, propyl orange, and butyl orange was investigated at 5, 15, 25 and 35°C in an aqueous solution. The amount of binding of the dye is much higher with this polyamide than with powdered Nylon 66 reported previously,1 although the former polymer has fewer amide end groups. The Van't Hoff plots of the first binding constant for the binding of butyl orange and propyl orange by powdered Nylon 612 exhibit a bell‐shaped curve, whereas the plots for methyl orange and ethyl orange do not. Maximal binding occurs at approximately 15°C for propyl orange and at about 25°C for butyl orange. This is the first instance where the peculiar temperature dependence of the binding constant has been found in the binding of propyl orange, whose hydrophobicity is less than that of butyl orange. These tendencies can be accounted for in terms of increased hydrophobic of butyl orange. These tendencies can be accounted for in terms of increased hydrophobic domains in powdered Nylon 612 and enhanced hydrophobic contributions in the binding process.

Liquid ammonia is effective at improving the strength, shrink resistance, and hand of cotton fabric. In this study, we apply a liquid ammonia (NH3) treatment to three regenerated cellulosic fabrics—rayon taffeta, cupro taffeta, and polynosic broadcloth— and subsequently process these with hot water and dry heat. We investigate the effect of the processes on crystal form, crystallinity, moisture regain, water absorption, and dyeing properties. Also, the mechanical properties of the NH3-treated fabrics are measured in relation to fabric hand. The diffraction intensity profiles of the rayon taffeta are unchanged by the NH3 treatment and subsequent heat processing. The profile of cupro taffeta is not changed by the NH3 treatment, but it is transformed to cellulose IIIII by subsequent hot water and dry heat processes. On the other hand, although the profile of polynosic broadcloth is transformed to cellulose IIIII by the NH3 treatment, the profile is not changed by hot water and dry heat. Furthermore, fabric crystallinity decreases with the NH3 treatment and increases somewhat after the hot water and dry heat processes. Water absorption and equilibrium dye uptake decrease with the NH3 treatment. Excellent washing shrinkage resistance is obtained with the NH3 treatment. The shearing and bending parameters of the rayon and cupro fabrics decrease somewhat with the NH3 treatment, so this treatment of regenerated cellulosic fabrics is effective at improving hand as well as washing shrinkage.

Cotton and wool fabrics were treated with low temperature oxygen plasma or en zymes or both and examined for their mechanical and dyeing properties. Plasma- treated cotton showed reduced strength, while the rate of weight loss in subsequent cellulase treatments decreased compared with untreated cotton. Equilibrium uptake of a direct dye remained unchanged regardless of plasma or cellulase treatment. The rate of dyeing increased, however, although the difference was slight, in the order of plasma treatment < untreated < cellulase treatment = plasma/cellulase treatment. Plasma pretreatment of wool caused an increase in strength and a higher rate of weight loss in the subsequent protease treatment. When wool was dyed with a leveling acid dye, equilibrium dye uptake did not change with plasma or protease pretreatment, but the dyeing rate increased with the plasma pretreatment With a milling acid dye, both increased greatly in the order of untreated < protease treatment < plasma treat ment < plasma/protease treatment. From these results, we assumed that plasma attacks the surface of the fiber, and the enzyme affects mainly the inner part of the fiber. This was confirmed by scanning electron microscopy. The polymerization of enzyme with a water-soluble carbodiimide did not show any strength retention effect in enzymatic treatment of cotton and wool.

The influence of the major grafting parameters (irradiation dose, reaction time, and inhibitor concentration) on graft polymerization of glycidyl methacrylate from its 10% solution in methanol onto nonwoven polypropylene upon irradiation with an electron accelerator in air was studied.

The mechanism of improvement in exhaustion and fixation of acid dyes in the recently reported low-temperature dyeing of silk fabrics with acid dyes in the presence of a hydrogen peroxide/glucose redox system was studied. The increases in dyeing rate and adsorption of acid dyes on silk fibers in the presence of the redox system could be attributed to the decrease in pH due to the decomposition of glucose with hydrogen peroxide but not to the covalent fixation of dyes on silk assisted by the free radicals.

Applying the electron‐beam preirradiation method in air the cation ‐ exchange fabric (CEF) containing sulfonic acid (R‐SO3H) groups was prepared by graft copolymerization of sodium styrenesulfonate with acrylic acid onto non woven polypropylene fabric. The effect of reaction conditions on the grafting yield and reaction mechanism was examined.The ion‐exchange properties towards Cu(II) and Co(II) ions of the CEF were investigated depending on the form of the CEF and a pH of the solution. It was found that the synthesized CEF contains both strong acid groups (R‐SO3H) and weak acid (R‐COOH) groups in almost equal proportion. The utilization of the CEF in Na+ form allows to make the best use of its ion‐exchange capacity.