Mechanical and surface properties are considered important in governing the physical strength of polymers. A commercially available oxo-biodegradable polymer additive, which has induced surface and mechanical property changes during photo-oxidation in low-density polyethylene (LDPE) films, has been studied. LDPE films containing the oxo-biodegradable additive were irradiated with ultraviolet (UV)-B lamps at 30 ± 1 1C for an extended time period. The changes manifested on the polymer surface and in the mechanical properties were studied with respect to surface wettability, surface morphology using scanning electron microscope, surface topology by atomic force microscopy, functional groups by Fourier transformed infrared spectroscopy, absorbance spectra by UV-visible spectroscopy and elongation at break and tensile strength through mechanical testing. The increase in the wettability and surface-free energy of the irradiated samples was attributed to the formation of hydrophilic groups on the polymer surface by photo-oxidation, which occurs by the exposure of PE to UV irradiation in the presence of air. The degree of reduction in the mechanical strength and surface property modifications in our study are appreciable through the use of an oxo-biodegradable additive added to LDPE film samples.

Polyhedral oligomeric silsesquioxane (POSS) viz; namely, Octa functional silsesquioxanes [octa amino (OAPS) and octa glycidyl (OG)] reinforced epoxy modified cyanate ester nanocomposites were prepared through intercrosslinked network. The intercrosslinking formation between cyanate ester and POSS was confirmed by Fourier transform infrared spectroscopy. The morphology of nanocomposites was studied using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and atomic force microscopy techniques. The electrical properties of the nanocomposites were evaluated by impedance analyzer. The influences of POSS macromer on the thermal and mechanical properties of epoxy modified cyanate ester nanocomposites were also addressed. The thermogravimetric analysis indicates that the thermal stability of the nanocomposites increases with increasing percentage of both types of POSS macromer. The dielectric constant and dielectric loss are decreased with increasing POSS concentration in the epoxy modified cyanate ester nanocomposites.

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The organic NLO material 2-nitro aniline and picric acid (2NAP) was synthesized, needle shaped single crystals of dimension 10 × 1 × 0.8 mm 3 were grown by slow evaporation solution growth technique from the saturated solution of the title compound in chloroform at ambient temperature. The material was characterized through elemental analysis, powder XRD, 1 H NMR, 13 C NMR and FTIR techniques. The various planes of reflection have been identified from the XRD powder pattern. The formation of the charge transfer complex was confirmed by UV-VIS spectroscopy. The thermal stability of the crystals was investigated using TG/DTA analyses techniques. The second harmonic generation (SHG) efficiency of the material was estimated using Nd: YAG laser as source.