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Cotton fabrics with antimicrobial properties were prepared by treatment with aqueous solutions of poly vinyl alcohol/zinc oxide (PVA/ZnO) nanocomposites and subsequently exposed to UV radiation. The ZnO nanoparticles, PVA/ZnO nanocomposite films, and treated cotton fabrics were characterized by transmission electron microscopy, Fourier transform infrared, X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. The antibacterial finishing of the treated cotton fabrics was evaluated toward gram-positive and gram-negative bacteria. J. VINYL ADDIT. FIG. 3. The X-ray diffraction patterns of pure poly vinyl alcohol and poly vinyl alcohol/zinc oxide nanocomposite films. FIG. 4. Scanning electron microscopy of (a) untreated cotton fabrics, (b) poly vinyl alcohol/zinc oxide nanocomposite treated samples.

Kinetics of radiation grafting of N-vinyl pyrrolidone (NVP) onto poly(ethylene terephthalate) (PET) fabric revealed the existence of four different processes. These are as follows: the grafting, the homopolymerization, the degradation, and the diffusion. The grafting process was followed by the increase in weight with the increase in irradiation time (t), while the homopolymerization and the degradation processes were evaluated from changes in the square root of the specific viscosity of the irradiated monomer solution (͌ sp ) with the increase in t. All processes were carried out at different NVP concentrations, different irradiation temperatures (T), and a dose rate 1.31 Gy s Ϫ1 . All processes followed first-order kinetics except the degradation process that followed a 0.6-order. The rate (R) and rate constant (k) of grafting and diffusion processes were found to increase with the increase in T, while the homopolymerization and degradation processes showed negative temperature dependence. The sum of R of the four processes was proportional to the initial NVP concentration, while k of the four processes was independent of T and has a value of 0.674 min Ϫ1 . The respective apparent activation energies of 24.0, 6.24, 6.84, and 2.5 kJ mol Ϫ1 were calculated for the four processes. The NVP molecules participated in each process and their energies were evaluated.

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In this study, cotton fabric was employed to achieve electronic textile by incorporating nano MnO2 and polyaniline as conductive materials. The treatment was accomplished via two consecutive steps, where different concentrations of MnO2 were initially applied by the ultrasound-assisted template method onto the cotton samples to synthesize nanoMnO2. The nano form of the metal oxides and polyaniline inclusion were demonstrated through a transmittance electron microscope. Thereafter, chemical oxidative polymerization of aniline over the nano metal oxide–loaded fabrics was performed. Structure, phase, and purity of as-treated fabrics were determined using X-ray diffraction and Fourier transform infrared spectroscopy. The thermal properties of the fabricated conductive samples were also tested. The electrical conductivity of the obtained (nano MnO2/polyaniline) modified cotton fabrics showed great enhancement by exposing the modified samples to gamma irradiation, as a posttreatment, to reach an optimum condition at 40 kGy, using 0.2 M MnO2. The recorded increment for electric conductivity was from 5.4 × 10−3 to 1.43 × 10−1 Ω−1. m−1 for both unirradiated and 40 kGy irradiated samples, respectively. Pseudo-capacitance of cotton/MnO2/polyaniline fabric electrode was tested using a three-electrode system. The assumption of (nano MnO2/polyaniline) cotton fabric conductivity was verified through a designed pseudo-capacitor as an important yet simple form of an energy storage device.

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Carrier‐free dyeing of radiation‐grafted polyester fabrics with disperse red dye was studied in the temperature range 283–363 K. 1‐vinyl 2‐pyrrolidone (NVP), acrylic acid (AA) or their mixture was used to graft poly(ethylene terephthalate) (PET) fabric. The effects of pH of the dye solution, graft yield (GY), dyeing time (t), dye concentration (C), and dyeing temperature (T) on the colour difference (CD) of PET fabric were studied. The best dyeing condition was achieved at pH 5.5. CD increases linearly with the increase in GY, with slopes depending on the type of grafted copolymer. CD increased rapidly as the dyeing time increased; this was followed by a relatively slow dyeing rate within a few minutes. The initial dyeing rate (R) was found to increase with an increase in C and T. The dyeing rates for all grafted samples followed 0.35‐order kinetics and are temperature‐independent. Average activation energy 9.26 kJ mol−1 is calculated for the dyeing process and is independent of the fabric treatment. Pre‐exponential rate constants 1976, 1839, and 1579 (CD/GY) s−1 were calculated for dyeing PET samples grafted with AA/NVP mixture, NVP and AA, respectively, while 1074 CD s−1 was evaluated for carrier dyeing of ungrafted fabric. Analysis of the kinetic parameters and the dyeing mechanism revealed that dyeing PET fabric was diffusion‐controlled. Grafting PET fabric improved significantly the dyeing affinity of the DR dye over ungrafted samples dyed in solutions containing a carrier. Copyright © 2005 Society of Chemical Industry