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Nanocomposites of poly(vinyl alcohol) (PVA)/poly(vinyl pyrrolidone) (PVP)/silver-doped zinc oxide (Ag-doped ZnO) ternary blends were prepared and characterized by Fourier transform infrared (FTIR) spectroscopy, ultraviolet (UV), scanning electron microscopy (SEM), X-ray diffraction (XRD), Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and conductivity studies. The FTIR and UV spectrum indicated the intermolecular interaction between the polar part of blend and the metal oxide nanoparticles. SEM and XRD patterns ascertained the structurally ordered arrangements of nanoparticles within the polymer matrix. The DSC results showed that the addition of Ag-doped ZnO particles to PVA/PVP decreases the thermal behavior such as glass transition and melting temperature of the blend. The TGA study indicated that the composites attained better thermal resistance than a pure blend and the thermal stability of the composite increases with an increase in the concentration of nanoparticles. The electrical properties such as AC conductivity and dielectric properties of the composites were increased with an increase in content of nanoparticles up to a certain concentration (5 wt%), and thereafter the value was found to decrease. C

In this study, we focused on the fabrication of poly(vinyl alcohol) (PVA)/poly(vinyl pyrrolidone) (PVP)/sericin composites via a simple solution-blending method. The composites were characterized by Fourier transform infrared (FTIR) spectroscopy, UV spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry, thermogravimetric analysis (TGA), and measurements of the conductivity, tensile strength, and antibacterial activity against Staphylococcus aureus. The results of FTIR and UV spectroscopy implied the occurrence of hydrogen bonding between sericin and the PVA/PVP blend. The structure and morphology, studied by XRD and SEM, revealed that the sericin particles were well dispersed and arranged in an orderly fashion in the blend. The glass-transition temperature (T g ) of the composite was higher than that of the pure blend, and the T g value shifted toward higher temperatures when the volume fraction of sericin increased. TGA indicated that sericin retarded the thermal degradation; this depended on the filler concentration. The mechanical and electrical properties, such as the tensile strength, alternating-current electrical conductivity, dielectric constant, and dielectric loss of the composites, were higher than those of the pure blend, and these properties were enhanced when the concentration of sericin was increased up to 10 wt % filler content, whereas the elongation at break of the composite decreased with the addition of sericin particles. The antibacterial properties of the composite showed that sericin had a significant inhibitory effect against S.

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Nanocomposites based on poly (n-butyl methacrylate) (PBMA) with various concentrations of titanium dioxide (TiO 2 ) nanoparticles were synthesised by in situ free radical polymerisation method. The formation of nanocomposite was characterised by FTIR, UV, XRD, DSC, TGA, impedance analyser and flame retardancy measurements. FTIR and UV spectrum ascertained the intermolecular interaction between nanoparticles and the polymer chain. The XRD studies indicated that the amorphous region of PBMA decreased with the increase in content of metal oxide nanoparticles. The SEM revealed the uniform dispersion of nanoparticles in the polymer composite. The DSC and TGA studies showed that the glass transition temperature and thermal stability of the nanocomposites were increased with the increase in the concentration of nanoparticles. The conductivity and dielectric properties of nanocomposites were higher than pure PBMA and the maximum electrical property was observed for the sample with 7 wt% TiO 2 . As the concentration of nanoparticles increased above 7 wt%, the electrical property of nanocomposite was decreased owing to the agglomeration of nanoparticles in the polymer. Nanoparticles could impart better flame retardancy to PBMA/TiO 2 composite and the flame resistance of the materials improved with the addition of nanoparticles in the polymer matrix.

In this study, we report the preparation of polymer blend nanocomposites based on chitin (CT)/cashew gum (CG) with various contents of magnetite nanoparticles (Fe3O4). The fabricated nanocomposites were characterised by FT infrared (FTIR), X‐ray diffraction (XRD), high‐resolution transmission electron microscopy (HRTEM), magnetic property (vibrating sample magnetometry (VSM)), differential scanning calorimetry (DSC), thermogravimetry (TGA) and impedance analyser. FTIR study revealed the characteristic absorption and shifts of peaks of the blend matrix, the shifts being attributed to the intermolecular interaction of Fe3O4 nanoparticles with CT/CG segments. The amorphous domain of the blend decreased with an increase in the concentration of nanoparticles was observed from XRD analysis. The HRTEM images showed the uniform arrangement of nanoparticles within the CT/CG network. VSM studies showed the ferromagnetic nature of the blend composite with an increasing saturation of magnetism with super‐paramagnetic behavior. DSC and TGA results revealed that the glass transition temperature and thermal stability of the composites were increased by the addition of magnetite nanoparticles. AC and dielectric properties were much improved in the entire range of frequencies due to the interaction with Fe3O4 nanoparticles. The role of nanoparticles on mechanical properties has been carefully studied. The tensile strength and hardness of magnetite filled nanocomposites become significantly higher in comparison to unfilled compounds and the nanocomposite with 10 wt. % of nanoparticles showed the maximum tensile strength. POLYM. COMPOS., 39:E540–E549, 2018. © 2017 Society of Plastics Engineers

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