A study on the possibility of the preparation of superabsorbent hydrogels based on crosslinked carboxymethyl cellulose polymer and acrylamide monomer through electron-beam irradiation was carried out. The effects of the irradiation dose and polymer-monomer compositions on the crosslinking density were studied. The hydrophilic properties of the superabsorbent hydrogels were identified by the swelling percentage. The prepared hydrogels had higher swelling in distilled water than in salt solutions. Moreover, the hydrogels exhibited the highest swelling at pH 7. Also, increasing the temperature up to 508C caused an increase in the swelling. The thermal properties of the hydrogels were characterized with thermogravimetric analysis. The use of the prepared superabsorbent hydrogels for the growth of rice was also investigated through the water-retention property. The water retention in the soil was enhanced with the hydrogels. Superabsorbent hydrogels based on carboxymethyl cellulose polymer and acrylamide monomer could be considered as water-managing materials for agriculture and horticulture in desert and droughtprone areas.

Composite fabricated from starch and different concentrations of clay was prepared by solution casting method. The casted film was irradiated to different gamma irradiation doses 10, 20, 30, and 40 kGy. The dispersion of clay into starch was investigated by using X-ray diffraction (XRD). The structural morphology of the composite was measured by scanning electron microscope and infrared spectroscopy. Film properties, such as water vapor transmission, mechanical, and thermal properties were also measured. The gel content and swelling behavior of the starch/clay composite were investigated. It was found that the gel content increases with increasing clay content and irradiation dose. The results obtained indicate that the starch/clay composite showed an increase in the tensile strength, thermal stability. Moreover, there is a decrease in water vapor transmission (WVRT) which improves its barrier properties. Both XRD and infrared spectroscopy showed that starch can be intercalated into the clay galleries. Also antibiotic drug Chlortetracycline HCl was loaded into the starch/clay composite by direct adsorption method. Chlortetracycline HCl adsorption capacity of composite was found to increase from 1.13 to 4.20 mg Chlortetracycline HCl per gram dry film with increasing amount of drug concentration. In vitro drug release studies in different buffer solutions showed that the basic parameters affecting the drug release behavior of the film are pH of the solution, drug concentration, and time.

Hydrogels for this study were prepared from a mixture of carboxymethyl cellulose (CMC) and different concentration of clay using freezing and thawing cycles followed by electron beam irradiation. The introduction of montmorillonite (MMT) up to 4% leads to an increase in the gel fraction and an improvement in water resistance indicating that the clay is well dispersed within the polymer matrix. Their swelling (%) of the hydrogel in distilled water and different physiological fluids, such as physiological saline water and synthetic urine, were evaluated. These results suggest that the maximum swelling (%) in water reached 3559% compared to the dry hydrogels but still maintained its steady appearance. Moreover, the hydrogels exhibited smart swelling and shrinking in NaCl and synthetic urine. The surface morphology and thermal properties of these hydrogels were characterized by scanning electron microscopy and thermogravimetric analysis (TGA). The ability of the prepared hydrogel to absorb and retain a large amount of water and simulated urine was measured. The results suggested the possible use of CMC/ MMT composite hydrogels in the personal care product industry.

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