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Ceramic filler modified polymer blends are more in demand due to their excellent compatibility, easy processing and cost‐effectiveness. In the present work, we modified Polymethyl methacrylate (PMMA)/Polystyrene (PS) blends using solution blending with untreated (UT) and DC glow discharge plasma‐treated (air plasma treated‐APT) potassium hexatitanate (K2Ti6O13). Chemical bonding of virgin and modified blends was confirmed by Fourier transform infrared spectrophotometer (FTIR). Decreased structural defects and imperfections of KTO were confirmed by Raman spectroscopy. Modified surface morphology and elemental analysis were detected by scanning electron microscopy (SEM) and energy‐dispersive X‐ray analysis (EDAX). The quantification of particle size distribution has been determined by Zetasizer. Increased degree of crystallinity and decreased average crystallite size after plasma treatment were determined by X‐ray diffraction. Increased dielectric constant from ~22–200 and decreased loss up to 0.7 were analyzed by impedance analyzer. Lee's disc probe was deployed to confirm the optimized thermal conductivity of the modified blend system. By Differential Scanning Calorimetry, glass transition temperature of modified polymer blends was investigated. The change in surface from hydrophobic to hydrophilic by plasma exposure was confirmed by surface goniometer. However, the enhanced dielectric performance of modified PMMA/PS/KTO polymer blends may be suitable for flexible energy storage devices and gadgets. [ABSTRACT FROM AUTHOR]

Disperse dye red 1 (DR1) and carbon nanoparticles (CNPs) were doped separately to form polymer dispersed liquid crystal films, namely, DPDLC & CPDLC. Nematic liquid crystal (LC) and photopolymer NOA-65 were used to prepare these composite films using polymerisation-induced phase separation (PIPS) technique. In this research work, it is demonstrated that the minute concentration (0.05% wt./wt.) of DR1 and CNPs controls the LC droplet alignment and LC droplet size in polymer dispersed liquid crystal (PDLC) film. The effect of DR1 and CNPs on PDLC film has been investigated in terms of LC droplet size, transition temperature, voltage-transmittance characteristic, contrast ratio, response time, haze, and dielectric measurements. The obtained results reveal that the threshold voltage values of the composite film get reduced from 34.87 V (undoped) to 10.19 and 9.26 V, for 0.05% of DR1 and CNPs doping, respectively. The DR1 (0.05%) doped film shows improved contrast of the undoped film as compared to CNPs (0.05%) film, whereas CNPs (0.05%) doped film shows a faster response time of 2.81 ms as compared to DR1 (0.05%) doped film (3.14 ms). Dielectric analysis of undoped, DPDLC, and CPDLC films represents Debye type relaxation mode. [ABSTRACT FROM AUTHOR]

The surface of a polypropylene (PP) film was modified using acetone and acetone/oxygen. The chemical nature and stability of the surface modification was studied by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM).

Surface activation and functionalization by plasma treatment have a significant role in the hydrophilic and hydrophobic modification of surfaces for applications in distillation, separation, and purification processes. In this work, we have demonstrated the effective hydrophilic modification of poly(vinylidene fluoride) (PVDF), poly(acrylonitrile) (PAN) and NH2-functionalized multiwall carbon nanotube (MWCNT) blends in 5 min of air plasma treatment. Porous and ablated morphology was observed by subjecting the blends under scanning electron microscope (SEM). The hydrophobic state of the untreated surfaces was transformed into the hydrophilic state due to plasma treatment which was confirmed by water contact angle (θ) measurement. Concerned to the θ value, an increase in the surface free energy (γSE) and the work of adhesion (WAD) was found. To underpin the effect of air plasma and its physiochemical influence on the surfaces, Fourier transform infrared (FT-IR) spectroscopy analysis and atomic force microscopy (AFM) studies were done. The IR analysis supports the change in chemical functions (C≡N), and from the AFM study, the root mean square (RMS) roughness was increased for all the plasma treated samples. The viability of plasma treatment and its influence on surface modification was explored and addressed by correlating the results of surface analysis. [ABSTRACT FROM AUTHOR]

The present investigation describes the effect of various plasma operating parameters on the degradation efficiency of azo dye acid orange 7 (AO7) molecules in wastewater using a non-thermal atmospheric pressure plasma jet. The de-coloration and degradation of argon plasma-treated AO7-containing solutions were investigated using UV-Vis spectroscopy and high-performance liquid chromatography (HPLC). Information on the reactive species involved during the plasma treatment was examined in detail by optical emission spectroscopy (OES). The species such as OH• and H2O2 generated during the treatment processes were also investigated by means of spectroscopy. The change in pH and total organic carbon (TOC) of plasma-treated AO7-containing aqueous solutions were also investigated. The toxicity of plasma-treated AO7-containing aqueous solution was estimated by antibacterial analysis using agar well diffusion method against two different bacteria’s such as Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria. The OES results confirmed the generation of various reactive species such as OH• radicals, O, NO• and other exciting species of argon (Ar) during the treatment and these reactive species are responsible for the degradation of AO7 dye molecules in aqueous solution as confirmed by UV-Vis spectroscopy and HPLC. Furthermore, this investigation confirmed that the degradation process of the AO7 solution is highly dependent on the plasma operating parameters, which is further confirmed by TOC and pH analysis. The bacterial analysis demonstrated that the plasma-treated AO7 water did not show any considerable antibacterial activity against the bacterial, that is, plasma-treated AO7 unveiled non-toxicity against S. aureus and E. coli bacteria. [ABSTRACT FROM AUTHOR]