Nanorods of Sb 2 S 3 have been synthesized by a surfactant assisted hydrothermal method. The formation of nanorods through flowerlike morphology with an intermediate straw tide like structure has been depicted by scanning electron microscopy (SEM) study. This type of observation is the first of its kind for this material, and it has been explained on the basis of a two step heterogeneous nucleation-growth mechanism followed by crystal splitting. Raman spectroscopy of the nanorods has been carried out to provide an idea about their purity. An increase in the band gap is observed for Sb 2 S 3 with nanorod-type morphology. Photoluminescence (PL) shows no sign of quantum confinement effect, though a large increase in intensity for nanorods has been observed compared to the flowerlike morphology.

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We have investigated the agglomeration behaviour of two types of multi-walled carbon nanotubes (MWNTs; N-MWNTs and D-MWNTs), which have different chemical functionalities, average diameter, varying extent of agglomeration and agglomerations. The properties were altered by varying the agglomerated structure. The strength of the MWNT agglomerates was estimated via nanoindentation. The work done to indent D-MWNT agglomerates (3910.3 × 10(-8) erg) was higher than for N-MWNTs agglomerates (2316.4 × 10(-8) erg). An organic modifier, the Li salt of 6-aminohexanoic acid (Li-AHA), was used to deagglomerate the MWNTs in an aqueous medium. The stability of the aqueous dispersion of Li-AHA-modified MWNTs was analyzed by UV-vis spectroscopy and zeta potential measurements. An increase in Li-AHA concentration increased the dispersion of MWNTs in the aqueous medium. Furthermore, the mechanism of dispersion of the two types of MWNTs in the aqueous medium in the presence of Li-AHA was determined based on the electrostatic charge repulsion between the negatively charged species. A fluorescence-activated cell sorting technique was used to assess the debundling of MWNT agglomerates in the aqueous medium. We examined the morphology-property relationship in Li-AHA-modified MWNTs.

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Binary blends of acrylonitrile-co-butadiene rubber and ethylene propylene diene monomer rubber are immiscible. However, they can be made compatible by addition of a third elastomer viz., chlorinated polyethylene or chlorosulphonated polyethylene in small concentrations. Various sophisticated analytical techniques, e.g., ultrasonic velocity measurements in solutions, infrared spectroscopy of solution cast films, thermo-mechanical analysis, processing characteristics through rubber process analyzer (RPA-2000), determination of the vulcanizate properties, and also phase morphology studies by atomic force microscopy have been made to elucidate compatibility and its effect on end-use properties of the evolved blends.

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Binary blends of a reactive ketone based polymer with liquid crystalline polymer (LCPA-950) were studied. The main properties required are flexibility and thermal resistance of material in presence of polyphosphazene, which acts as a compatibilizer. It has been observed that with the addition of LCP the composites showed reduced viscosity during blending and changes in the crystallization of the LCP phase. FTIR study showed that there was a partial interaction between the PEEK and LCP in presence of polyphosphazene. Polyphosphazene is miscible with both PEEK and LCP, which was evident from DMA results. The thermal stability of the composites has been studied by DTA/TGA. The thermal analysis of the blends showed that the degradation process is accelerated by blending, but with the addition of polyphosphazene the onset temperature of first degradation slightly shifted towards higher side than the PEEK/LCP blend. Measurement of the tensile properties showed an increase in the elongation as well as enhanced modulus and strength. From SEM micrographs of tensile fractured surfaces, it was revealed that there is good adhesion between the matrix and dispersed phase upon addition of polyphosphazene to ketone based polymer (PEEK) with LCP.