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The monomer 1-(isopropylamino)-3-(1-naphthyloxy)-2-propanoacrylate (IANOPA) and monomer 1-(isopropylamino)-3-(1-naphthyloxy)-2-propanomethacrylate (IANOPMA) were synthesized by treating 1-(isopropylamino)-3-(1-naphthyloxy)-2-propanol with acryloylchloride/methacryloyl chloride. The above esterification reactions were carried out in the presence of triethylamine. By employing the free radical polymerization method, the synthesized monomers were converted into polymers by using an initiator 2, 2′-azobisisobutyronitrile in the presence of nitrogen environment at 70±2°C. The monomers and polymers were characterized by various techniques such as FT-IR, UV, 1H NMR, and 13C NMR spectroscopic analyses. Further, differential scanning calorimetry (DSC) was used to estimate the glass transition temperature (Tg). Gel permeation chromatography (GPC) was used to estimate the molecular weight of the polymers. In addition, monomer and polymer surfaces’ morphology was analyzed using SEM analysis. As a primary application, the effectiveness of synthesized monomers and polymers was explored as antibacterial agents against gram-positive bacteria (Staphylococcus aureus) and gram-negative bacteria (Pseudomonas aeruginosa) which were measured from their inhibitory zone diameters. Further, the synthesized polymers, poly-IANOPA and poly-IANOPMA, were utilized for the uptake ability study of heavy metal ions such as Zn2+, Cu2+, Ni2+, and Pb2+ present in water sources by equilibrium method.

The cobalt oxide (Co3O4) nanomaterials were prepared by coprecipitation synthesis technique by maintaining the pH of the mother solution at 7, 8, and 9. The prepared nanomaterials were subjected to structural and optical characterizations, and the results were examined. The optical absorption spectral studies reveal that the two absorption bands indicate ligand–metal coordination. The photoluminescence spectra contain emission peak at 488 and 745 nm due to size and shape of the synthesized materials. The magnetic nature of the samples was identified from the hysteresis loop traced by vibrating sample magnetometry (VSM). The Fourier transform infrared (FT-IR) spectrum of Co3O4 nanomaterials reveals two sharp bands absorbed in 584 and 666 cm-1. This ascribes to the Co-O and O-Co-O stretching, respectively. As the pH of the solution varied from 7 to 10, the SEM image authenticates the transformation of Co3O4 nanomaterials morphology from spherical to cubic to agglomerated shape. From the UV-Vis spectra, two absorption bands around 473 nm and 762 nm are observed for the materials prepared at pH 7 and 8. But at pH 9, these two peaks were shifted towards higher wavelengths 515 nm and 777 nm. The observed ferromagnetic nature of Co3O4 nanomaterials clearly show the role of surface spins and surface morphology on the magnetic properties of Co3O4 nanomaterials. The cyclic voltammetry (CV) curves show the rectangular type of voltammogram. This is an indication of good charge propagation with the electrodes. The Nyquist plots of Co3O4 nanomaterials have a semicircle in the high frequency region and a vertical line in the low frequency region. The results suggest that Co3O4 is found to be a promising material for the fabrication of light-emitting diodes, solar cells, and optoelectronic devices.

Substituted pyrazolyl derivatives were synthesized through Suzuki cross coupling of aromatic boronic acid with heterocyclic halide using newly synthesized nano-Pd/chitosan catalyst by the water-mediated green synthesis methodology. The reactivity of the nano-Pd catalyst was highly enhanced by incorporating palladium nanoparticles with a biopolymer chitosan matrix. The synthesized nano-Pd/chitosan catalyst was studied thoroughly for its structure, morphology, and other fundamental aspects such as the size and shape by various techniques including XRD, FESEM, and EDAX analyses. The scope of the catalyst was disclosed by their great stability with remarkable reusability for Suzuki cross-coupling reaction with twelve different boronic acids under the green synthetic methodology.

Acetophenone derivatives are eco-friendly corrosion inhibitors to prevent corrosion of mild steel (MS) in acidic medium. In this work, the inhibition effect of 3-nitroacetophenone (3-NA) on the corrosion of MS in acidic medium (1 N HCl) was investigated using weight loss measurements, electrochemical measurements, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and quantum chemistry analysis. The studies were performed using different concentrations of inhibitors and at different temperatures. The results indicated that the inhibition efficiency of 3-NA increases with an increase in inhibitor concentration and reaches to a maximum of 64% at inhibitor concentration of 250 ppm at 30°C. The potentiodynamic polarization measurement indicated that 3-NA acts as mixed category of interdict. The adsorption of 3-NA on MS surface followed the Langmuir adsorption isotherm. The mode of adsorption of 3-NA on MS surface was further studied by quantum chemical calculations based on density functional theory (DFT). The results plainly revealed that 3-NA performs fairly as corrosion interdict for MS in acidic medium.

This work is based on the effect of different gamma doses with pre- and post-alpha-irradiated PM-355 polymer (polycarbonate of allyl diglycol). The phase crystallinity and structural analysis of the reference and irradiated PM-355 polymer were analyzed using an X-ray diffraction (XRD) study. It is revealed that the irradiation and etching reduce the %crystallinity but increase the crystallite size of the PM-355 polymer. The increase in crystallite size of PM-355 polymer after irradiation is supported by the scanning electron microscopic (SEM) analysis. The etching of the samples results in an increase in its track diameter. The optical band gap energy, measured by ultraviolet-visible (UV-VIS) spectroscopy, shows a decrement trend with the increase of gamma and alpha irradiation doses, and etching for all sets of samples under investigation. The number of carbon atoms per conjugation and per cluster has increased after gamma irradiation and etching. However, the increment is more pronounced for etched samples compared to nonetched ones. This indicates that etching results in a bigger size of cluster. Photoluminescence (PL) for both cases before and after etching has a dominant peak around 430 nm before and after irradiation, and change in peak intensity after irradiation confirmed that particle bombardment induced defects and clusters in the PM-355, which serves as nonradiative centers. The polymer can be used as a detector for gamma irradiation.

The aim of this work is to manage the waste product based on polyethylene (PE) films by recycling and reusing it as antistatic material for electronic packaging and electromagnetic interference (EMI) shielding material for protecting electronic equipment from interference of EM radiation. To achieve this, a conductive carbon black has been mixed with the PE waste at different weight percent values by ultrasonication via a solution mixing process. Mixing time for sonication was determined by ultraviolet-visible (UV-VIS) spectra. A differential scanning calorimetry (DSC) study showed that the low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE) are immiscible in their blend composition. The tensile properties of PE have reduced substantially after reprocessing. However, the addition of carbon black has improved its strength up to a certain loading. The electrical percolation threshold values, calculated using the classical power law and sigmoidal Boltzmann model, were obtained at 3.5 and 2.8 wt% loading of carbon black, respectively. The conductivity result revealed that 1-2 wt% carbon-loaded composites can be used as antistatic material. The composites, having carbon loading above 4 wt%, can be effective materials for EMI shielding application. The 10 wt% carbon-loaded composite exhibits EMI SE value 33 dB which means there is approximately 99.93% protection of EM radiation at the sample thickness of 1.0 mm. Moreover, FTIR analysis, thermal stability, AC conductivity, dielectric properties, permeability, and current-voltage characteristics are also discussed in detail. There is a substantial increment in thermal stability, and dielectric properties are observed with the addition carbon black loading within the polymer matrix.