Polyvinyl alcohol (PVA) was blended with starch (S) in presence of glacial acetic acid as crosslinking agent. The effect of blend ratio and molecular weight of PVA on the physical, thermal and mechanical properties of PVA/S blends were investigated using various techniques such as DSC, TGA, SEM, tensile strength, and solubility tests. Furthermore, biodegradability of the blend films was also studied. In addition, FTIR spectroscopy was used to check the hydrogen bonding interaction between PVA and S in the blends. The obtained results showed that the physico-mechanical properties are strongly dependent on the molecular weight and PVA content in PVA/S blends. DSC and SEM analyses of PVA/S blend showed a single glass transition temperature indicating the formation of completely miscible blends with a single phase due to the formation of hydrogen bonds between the hydroxyl groups of PVA and starch. In addition, PVA/S blend films exhibited good mechanical properties, thermal stability as compared with the pure PVA. More interestingly, the results showed enhancement in biodegradability of PVA/S blend films and particularly in moist soil, which can be exploited for manufacturing of biodegradable and environmentally friendly packaging materials at low cost.

New thermosensitive hydrogels based on N-isopropyl acrylamide and 2-hydroxyethyl acrylate were prepared in the presence of ammonium persulfate as an initiator using a free-radical technique. The thermal stability as well as the physical and chemical properties of the obtained hydrogel were studied by thermogravimetric analysis, differential scanning calorimetry and scanning electron microscopy. The swelling of the hydrogels was investigated by the cathetometer method. In order to use thermosensitive hydrogels as a carrier of antibiotics (lincomycin and gentamicin), several biological tests were performed. All samples of thermosensitive poly(N-isopropyl acrylamide) and 2-hydroxyethyl acrylate hydrogels containing medical substances exhibited antibacterial activity. The antibacterial activity of temperature-sensitive hydrogels naturally increases with increasing concentration of antibiotics in the carrier. The results obtained indicate a large amount of drug was released from the hydrogels with full retention of antimicrobial properties. These copolymers can be used as an antibacterial material in the field of medicine.

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The physical and mechanical properties of mortar containing copolymer lattices as chemical admixtures were investigated. Copolymer lattices used based on styrene and butyl acrylate were prepared in presence of potassium persulfate/sodium metabisulfite (KPS/NaMBS) as redox initiation system and a coemulsifier that consists of dodecyl benzene sodium sulfonate and polyvinyl alcohol (DBSS/ PVA). The results showed that the addition of copolymer lattices to mortar improves the physical and chemical properties of mortar. However, as the dosage of lattices increases, W/C ratio as well as workability increases while compressive strength and chemically combined water content decrease.