Study of electromagnetic shielding effectiveness of metal oxide polymer composite in their bulk and layered forms.

In this paper, we present the studies on electromagnetic interference (EMI) shielding effectiveness (SE) of KCrO-PMMA composites developed by two different methods: one in bulk form of thickness 1.2 mm and another by stacking twelve layers of thin films each of thickness 100 μm. The EMI SE of stacked twelve layers of 1.

Large-scale additive manufacturing with bioinspired cellulosic materials.

Cellulose is the most abundant and broadly distributed organic compound and industrial by-product on Earth. However, despite decades of extensive research, the bottom-up use of cellulose to fabricate 3D objects is still plagued with problems that restrict its practical applications: derivatives with vast polluting effects, use in combination with plastics, lack of scalability and high production cost. Here we demonstrate the general use of cellulose to manufacture large 3D objects.

Fabrication of a flexible UV band-pass filter using surface plasmon metal-polymer nanocomposite films for promising laser applications.

We introduce a strategy for the fabrication of silver/polycarbonate (Ag/PC) nanocomposite flexible films of (20 ± 0.01) μm thickness with different filling factor of surface plasmon metal using customized solution cast-thermal evaporation method. Structural characterizations confirmed the good crystallinity with cubic phase of Ag nanoparticles in PC films.

Fabrication of artificially stacked ultrathin ZnS/MgF2 multilayer dielectric optical filters.

We report a design and fabrication strategy for creating an artificially stacked multilayered optical filters using a thermal evaporation technique. We have selectively chosen a zinc sulphide (ZnS) lattice for the high refractive index (n = 2.35) layer and a magnesium fluoride (MgF2) lattice as the low refractive index (n = 1.

Synthesis of a low-band-gap small molecule based on acenaphthoquinoxaline for efficient bulk heterojunction solar cells.

A novel small molecule (SM) with a low-band-gap based on acenaphthoquinoxaline was synthesized and characterized. It was soluble in polar solvents such as N,N-dimethylformamide and dimethylacetamide. SM showed broad absorption curves in both solution and thin films with a long-wavelength maximum at 642 nm.

Enhancement of hydrogen gas permeability in electrically aligned MWCNT-PMMA composite membranes.

The multi-walled carbon nanotube (MWCNT) dispersed polymethylmethacrylate (PMMA) composite membranes have been prepared for hydrogen gas permeation application. Composite membranes are characterized by Raman spectroscopy, optical microscopy, X-ray diffraction, electrical measurements and gas permeability measurements. The effect of electric field alignment of MWCNT in PMMA matrix on gas permeation has been studied for hydrogen gas.

Effect of solvent and subsequent thermal annealing on the performance of phenylenevinylene copolymer: PCBM solar cells.

The morphology of the photoactive layer used in the bulk heterojunction photovoltaic devices is crucial for efficient charge generation and their collection at the electrodes. We investigated the solvent vapor annealing and thermal annealing effect of an alternating phenylenevinylene copolymer P:PCBM blend on its morphology and optical properties. The UV-visible absorption spectroscopy shows that both solvent and thermal annealing can result in self-assembling of copolymer P to form an ordered structure, leading to enhanced absorption in the red region and hole transport enhancement.

Microstructure change in poly(ethersulfone) films by swift heavy ions.

PES membrane of thickness 25 microm was irradiated by Cl(9+) ions of energy 100 MeV at IUAC, New Delhi. Microstructure changes due to exposure to high-energy ions were investigated by Fourier transform infrared (FTIR) and ultraviolet/visible (UV/vis) absorption spectroscopies, X-ray diffraction technique and by dynamic mechanical analysis (DMA). A significant loss of crystallinity is observed by the XRD data.

Characterization of asymmetric polymeric membranes by gas permeation.

Polycarbonate films (thickness 18, 25 and 38 microm) were irradiated by a beam of 100MeV Ni7+ ion. The permeability for hydrogen and carbon dioxide was measured from both sides of membrane at increasing etching time. These membranes show larger permeability from the irradiation side, than the reverse side indicating the formation of conical tracks and asymmetrical membrane.