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Synthesis of antimicrobial films for packaging applications is eminent fields of research. This study describes preparation of biodegradable Poly (PVA/PLA/ TiO 2 ) nanocomposite films was carried out by blending polyvinyl alcohol (PVA) and polylactic acid (PLA) doped with titanium dioxide (TiO 2 ) nanoparticles using solution casting method and then irradiated by γ-irradiation. The properties of the films were characterized by FT-IR, XRD, FE-SEM, TEM, TGA, and mechanical tests. The addition of TiO 2 nanoparticles (0.8 wt%) explored considerable effects on thermal stability of the films. Results of FE-SEM and TEM illustrated quite uniformly dispersion of TiO 2 nanoparticles with average size of 17.5 nm. The effect of γ-irradiation on nanocomposite films showed enhanced water resistance property and water vapor transmission rate. The water resistance property was achieved using PVA/PLA composition ratio (2/1). The antibacterial activity was evaluated against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria.Poly(PVA/PLA/TiO 2 ) nanocomposite film irradiated at 20 kGy displayed improved antibacterial activity and was selected for soil burial biodegradation tests. The biodegradation rate increased rapidly in the initial 12 weeks with significant changed morphology. The enhanced antibacterial efficiency and biodegradation property of the nanocomposite films suggest their possible use for development of packaging materials with low environmental impact.

The curing characterizations of natural rubber (NR) and styrene butadiene rubber (SBR) lattices and their blends with and without NR‐g‐MA and SBR‐g‐MA were studied by using oscillating disc rheometer methods. The minimum value for torque decreases with increasing NR in the blends and with the incorporation ofNR‐g‐MA and SBR‐g‐MA. The value of maximum torque increases with increasing of SBR in the blend and with the presence of (NR‐g‐MA and SBR‐g‐MA) is decreased. The mechanical properties of the samples were studied. The tensile strengths increased steadily with an increase of NR content in the blend. Thermal characteristics of these latex blends were studied by thermogravimetric analysis. Thermal degradation of these individual lattices and their blends were investigated with special reference to blend ratio and vulcanization techniques. As the SBR content in the blends increased their thermal stability was also found to increase. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers

The adsorption of the cationic dyes Rhodamine B (RB) and Crystal Violet (CV) on polyacrylamide/poly(acrylic acid) (poly(AAm/AAc), 25:25 % weightwise) and polyacrylamide/poly(sodium acrylate) (poly(AAm/AAcNa), 25:25 % weightwise) hydrogels was studied, employing the Langmuir and Freundlich isotherms. The results of swelling tests at pH 5.5 indicate that poly(AAm/AAcNa) hydrogel shows maximum percentage swelling (%S) was 4400 %. Moreover, the results show that the adsorption capacity is pH‐ and concentration‐dependent. At pH >5 adsorption of RB and CV increases due to ionization of COOH and COONa groups of (poly(AAm/AAc) and (poly(AAm/AAcNa) and interactions with the cationic groups of the dyes. However, at pH lower than 5, adsorption is still high, which can be explained by considering the formation of hydrogen bonds between the amino groups of the dyes and the COOH groups of the polymeric hydrogels. Moreover, the kinetics of adsorption follows a first‐order equation. Furthermore, scanning electron microscopy (SEM) micrographs of polymeric hydrogels doped with CV and RB have morphological differences from the pure form. Our data show that Rhodamine B adsorbs more efficiently on both polyacrylamide/poly(acrylic acid) and polyacrylamide/poly(sodium acrylate) hydrogels than CV. Copyright © 2004 Society of Chemical Industry