The instability in water of poly(vinyl alcohol) (PVA)/poly(carboxymethyl cellulose) (CMC) was improved through radiation‐induced grafting with a styrene monomer. The PVA/CMC blend graft copolymer was used as a sorbent for dye wastes normally released from textile factories. The factors that may affect the sorption process such as time, temperature, weight of the blend graft copolymer, and volume of the dye waste were investigated. The sorption of dyestuffs by the blend graft copolymer was determined by a method based on spectroscopic analysis. The results showed that the blend graft copolymer has a high affinity for basic, acid, and reactive dyes. Meanwhile, it was observed that the sorption of dyes is more effective at the high temperature of 70oC. Moreover, it was found that the sorption of dyes depends on the weight of the blend graft copolymer and does not depend on the volume of the waste solution. The sorption of the dyestuffs by a PVA/CMC graft copolymer may be considered to be a practical method to remove organic pollutants. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 136–142, 2001

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The role of certain cations as homopolymer inhibitors in the direct radiation grafting of acrylic acid to nylon-6 fabric was investigated. The grafting solution was methanol and water at a ratio of 30 : 70 ~01%. The maximum graft yield was obtained at 0.08 wt% when using Fez+ and at 0.7% for Fe3+. In addition, the graft yield obtained with the latter ion was higher than that for the former. Moreover, the presence of Na+ and K' salts in concentrations as low as 0.1 wt% caused an increase in the graft yield. The hydrophilic properties investigated indicated that the water absorption of nylon-6 fabric after 9 days increased by 44 times after grafting with poly(acry1ic acid) at 166% graft yield. This ratio became 123 times, when this graft copolymer was transformed to the sodium salt. These ratios became 105 and 490 times for the corresponding recrystallized forms, respectively. A study was made to gain a better understanding of the observed super water absorption using SEM and DSC analysis. SEM micrographs of the recrystallized copolymer indicated the formation of large pores with a dendritic structure. Moreover, DSC showed a decrease in both the heat of fusion and melting point. The grafted nylon-6 fabric showed a noticeable affinity for different dyestuffs. A. M. El-Naggar et al.The morphological structure of the graft copolymer of nylon-6 and its recrystallized form was also investigated. Some hydrophilic properties such as moisture and water regain, as well as super water absorption, were evaluated. EXPERIMENTAL MaterialsNylon-6 fabric. This was a knit weave type (84g/cm2) obtained from Middetex Company, Cairo, Egypt. It was scoured, hydrogen peroxide bleached and was not subjected to a finishing process. Before use, it was washed with a solution containing 5 g/litre Na,CO, and 1% of a non-ionic wetting agent (Sandopan) to remove any undesired materials, which may affect the grafting reaction.Dyestufs. Solar Orange (direct dye), Sandocryl Red B6B (basic dye), Levafix Brilliant Red E-4BA (reactive dye) and Samaron Blue FBL (disperse dye); the first two dyes were kindly supplied by Sandoz, Switzerland, while the third and fourth were from Bayer and Hoechst, Germany, respectively. Monomer and chemicals.Acrylic acid was of purity 99% (Merck, Germany) and was used as received. The other solvents and chemicals were of pure grade and were used without further purification. MethodsGrafting procedure. The direct radiation grafting method was used in the presence of air; the nylon-6 substrates were placed in contact with the grafting solution. The different additives, such as metal salts, were added to the grafting solution, which was then exposed to gamma radiation. Irradiation was carried out at a dose rate of 0.5-0.45 Mrad/h in the cobalt-60 gamma source (made in India) of the National Center for Radiation Research and Technology, Cairo, Egypt. The grafted nylon-6 substrates were washed thoroughly with hot distilled water to remove unreacted monomer and surface homopolymer. Then the grafted substrates were extracted in...

In the present work, polymeric composites were prepared for coating floors and swimming pools in dark colors. This was achieved through the use of a polymer coating solution added to fine cement with weight percentage (wt%) values of 5, 10, 15, 20, and 25 to obtain dark-colored (gray) composites. Mortar samples were prepared using the adhesion test. The contact angle and adhesion strength were studied for the prepared samples concerning the effect of changing the weight ratio of additive cement on water absorption. Also, the antibacterial activity was tested for the prepared coatings. The results showed that the contact angle increases with increasing the weight ratios of additive cement, which indicates that the prepared coating is not hydrophilic and water-impermeable. Besides, the adhesion was shown to increase with increasing the weight ratio of cement. According to the antibacterial activity analysis, it was found that the highest efficacy for killing Staphylococcus areus was observed at cement ratios of 5 and 15 wt%, whereas no activity was observed against Escherichia coli.

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