Three push–pull aminopyridine derivatives having D–π–A, D–(π–A)2, and D–(π–A)3 arrangements were examined as model organic chromophores capable of intercalation into inorganic layered materials.

The current study concerns the preparation and characterization of marmoreal solid surface materials based on polymethylmethacrylate (PMMA) nanocomposites filled with waste stones of marble, granite and basalt. Hydrophilic nanosilica and clay Halloysite nanotubules (HNTs) were the two types of nanofillers used to prepare PMMA/stone waste nanocomposites. The effect of nanofiller type and stone nature was investigated by Rockwell hardness, flexural strength, impact toughness, abrasion loss, water absorption and luminous transmittance measurements. The prepared artificial stone samples have an eye-catching decorative effect of alabaster when lighted from rear using a low energy light source.

Higher concentrations of ceramic fillers induce brittleness in the ceramic/polymer hybrids which restrict their applications to limited fields especially when such hybrids are prepared for their use as dielectrics. We have synthesized and characterized different BaTiO3-polypyrrole (PPy) composites by changing the concentration of BaTiO3 from 1% by weight of PPy taken to 5 wt % to explore its effect on the dielectric parameters of the final product and found that the BaTiO3-polypyrrole composite with weight ratio of 0.05:1 exhibited highest dielectric constant, lowest dielectric loss and thermally most stable. All the composites were prepared using in-situ polymerization of pyrrole in an aqueous dispersion of low content of BaTiO3 in the presence of small amount of Hydrochloric acid. These composites were characterized for their microstructure and crystallinity by X-ray diffractometer (XRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) while thermal stability by thermo gravimetric (TGA) analysis. An impedance analyser (LCR meter) was utilized to investigate the dielectric parameters. FT-IR data confirmed the presence of the two phases and their interaction, inferred from the shifting of normal PPy peaks. The data obtained from XRD confirmed the presence of crystallites of 2.8 to 5 nm with dominant crystallinity of the filler, TGA analysis (25 to 600 °C) confirmed the higher thermal stability induced on successive addition of the filler into the prepared composites as compared to that of pure PPy in a wide temperature range which is unusual for such a low % age addition of the filler. The SEM analysis together with XRD results reveal that the successive introduction of BaTiO3 particles produced crystallites of 2 to 5 nm size which bonded together and changed the hemispherical shaped larger grains of the matrix to regular shaped smaller grains. The dielectric constant of the composites was enhanced with filler contents from 178 to 522 at 1 MHz for 1 wt % and 5 wt % BaTiO3 respectively. It was concluded that the introduction of BaTiO3 into the polymer matrix with this new procedure has greatly affected the polymerization process, thermal stability, morphology and dielectric properties of the host matrix and has resulted in a novel series of the composites which may have broad applications.

A new type of chalcogenide crystals Tl 4 SnS 3 , Tl 4 SnSe 3 , Tl 4 SnTe 3 easily processing by external IR laser light is fabricated. For the titled crystals linear electrooptical effect was induced by external IR polarized light formed by two coherent beams of Er:glass nanosecond laser at fundamental wavelength 1540 nm. The detection of the electrooptical coefficient was performed by continuouswave 1 W CO 2 laser at probing wavelength 10.6 lm. The origin of the effect is caused by an occurrence of the thin (up to 50 nm) photoexcited nanosheets which forms near the surface space charge density non-centrosymmetry. The relaxation of the electrooptics after switching off of the photoinduced Er:glass laser beam is explored for different types of samples at different power densities. The crystals may be used for IR optical triggering.