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The present study reports on a simple and very efficient solution mixing method for the preparation of functionalized multiwalled carbon nanotube/polyaniline nanocomposites (f‐MWCNT/PANI) for electromagnetic interference (EMI) application. The synthesized composites have been characterized by different physiochemical techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffractometry (XRD), and Fourier transform infrared (FT‐IR) spectroscopy. The electron microscopy analysis of nanocomposites reveals the good dispersion and agglomeration of CNT in PANI matrix at higher concentration. X‐ray study shows the higher crystallinity of PANI with the addition of f‐MWCNT. FTIR spectroscopy has confirmed the interactions of the carbonyl group of f‐MWCNT with the quinoid ring of PANI. The resulting f‐MWCNT/PANI nanocomposites (0 to 21 vol% CNT) shows higher electrical conductivity than that of pure PANI due to the formation of conducting path between CNT and PANI matrix. The increased electrical conductivity of nanocomposites also improved the estimated EMI shielding. The percolation threshold was found to occurs at 0.1 vol% of f‐MWCNT, where the DC electrical conductivity started to increase abruptly. The one‐order increment in electrical conductivity was observed which is 12 times more than that of pure PANI. The DC electrical conductivity of nanocomposite at 3.3 vol% and 13.9 vol% of f‐MWCNT was 1.6 × 10−1 S/cm and 1.8 × 10−1 S/cm, respectively. In addition, the estimated EMI shielding of nanocomposites at 3.3 vol% of f‐MWCNT and beyond it was found to be 12dB. POLYM. COMPOS., 39:3858–3868, 2018. © 2017 Society of Plastics Engineers

An attempt was taken to synthesize two types of polyaniline (PANI) with and without solvent followed by drying in air and vacuum oven conditions resulting different morphologies. The PANIs were prepared by chemical oxidative polymerization and studied with respect to their morphological features. Scanning electron microscopy, thermogravimetric analysis, X-ray diffractometry, Fourier transform infrared spectroscopy, and ultraviolet-visible spectroscopy techniques were used for the characterization studies. The PANI synthesized with a solvent had a mixed morphology (fibrillar and granular), whereas PANI synthesized without a solvent had only a granular morphology. The direct-current electrical conductivities of the samples were evaluated with an electrometer. We observed that the PANIs with mixed morphology (with solvent) were more electrically conducting than those with a single morphology (without solvent). On drying in vacuo, the conductivity of PANI decreased from 3.3 3 10 22 to 0.3 3 10 22 S/cm with solvent treatment, whereas it decreased from 0.1 3 10 22 to 0.3 3 10 23 S/cm without solvent treatment. V C 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44091.

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In the present work, an experimental investigation on wire electrical discharge machining (WEDM) of Monel-400 has been presented. Monel-400 is a nickelcopper-based alloy, mostly employed in ships and corrosion-resisting applications. Four input WEDM parameters namely discharge current (Ip), pulse-on time (Ton), pulseoff time (Toff) and servo voltage (SV) have been investigated and modeled for two performance characteristics namely machining rate (MR) and surface roughness (SR). Effect of WEDM parameters has been discussed using response surface graphs. Using analysis of variance, quadratic model is found significant for MR while two factors interaction (2FI) model has been suggested for SR. To optimize multi-performance characteristics, desirability function has been employed. Corresponding to highest desirability, the optimal combination of discharge parameters is Ip: 103 A; Ton: 113 ls; Toff: 37 ls and SV: 50 V. The effect of discharge energy on surface morphology has also been examined. High discharge energy increases the extent of surface damage and results in large size and overlapped craters on machined surface. Low discharge energy and high value of Toff result in minimum defects on machined surface. Trim cutting operations were performed at low discharge energy using different wire offset values. Result shows that surface finish can be improved significantly after a single trim cut irrespective of high discharge energy in rough cut.

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At present, people more actively pursuing biodegradable-based food packaging to lower the environmental problems of plastic-based packaging. Starch could become a promising alternative to plastic because of its properties (easily available, nontoxic, tasteless, biodegradable, ecofriendly, and edible). This review article is focused mainly on the impact of the properties of starch-based biodegradable films, such as their thickness, morphology, and optical, water-barrier, mechanical, oxygen-barrier, antioxidant, and antimicrobial properties, after the incorporation of additives, and how such films fulfill the demands of the manufacturing of biodegradable and edible food-based film with preferable performance. The incorporation of additives in starch-based films is largely explained by its functioning as a filler, as shown via a reduction in water and oxygen permeability, increased thickness, and better mechanical properties. Additives also showed antimicrobial and antioxidant properties in the films/coatings, which would positively impact the shelf life of coated or wrapped food material.