Synthesis and Characterization of Poly(o-chloroaniline)/TiO2 Nanocomposites for Photocatalytic Degradation of Direct Yellow 50 Dye in Textile Wastewater

<p>The nanocomposites of poly(o-chloroaniline) with titanium dioxide have been prepared via chemical oxidative polymerization technique using o-chloroaniline monomer and titanium dioxide nanoparticles for photocatalytic application. The different composites were prepared by varying the load percentage of titanium oxide nanoparticles (TiO2 NPs) in polyorthochloroaniline (POCA) matrix. The synthesized composite materials were characterized by Scanning electron microscopy (SEM), X-Rays diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques. The POCA/TiO2 nanocomposites were further applied to evaluate the photocatalytic degradation potential towards direct yellow 50 (DY50) dye in an aqueous medium under ultraviolet radiations.</p>

Synthesis, Structural, Morphological and I-V Characteristics of Polyaniline-MgCl Composite

Composite of polyaniline-MgCl has been synthesized using oxidative polymerization method. Synthesized samples were characterized for structural analysis using FTIR and XRD. Morphological studies were carried by SEM micrographs. Current-Voltage (I-V) properties are obtained through Kiethly source meter. FTIR spectrum of polyaniline-MgCl composite indicates all the characteristic peaks of polyaniline. X-ray diffraction patterns represented the amorphous nature of polyaniline-MgCl composite. SEM micrographs confirmed the presence of MgCl particles in polyaniline matrix. I-V characteristics have shown the ohmic type behavior of polyaniline and polyaniline-MgCl composite.

Evolution of the Surface Structure and Functional Properties of the Electroconducting Polymer Coatings onto Porous Films

Composite systems containing electroconducting polymer coatings (polyaniline and polypyrrole) applied to porous films of semicrystalline polymers (polyethylene, polypropylene, and polyvinylidene fluoride) have been prepared. Porous supports were obtained in the process based on polymer melt extrusion with subsequent annealing, uniaxial extensions, and thermal stabilization. Conducting coatings were formed by the oxidative polymerization of the monomers directly onto the porous supports. The structure (overall porosity, permeability, pore sizes, factor of orientation) and morphology (specific surface and character of the film surface) of the supports were characterized by sorptometry, filtration porosimetry, atomic force microscopy (AFM), and X-ray scattering techniques. It was observed that the porous supports have a strongly developed relief surface which is formed in the pore formation process. It was proven by scanning electron microscopy (SEM) that the porous supports have an oriented structure, and the surface of the composites is defined by the morphology inherent in the conducting component. It was shown that these composites (porous support/conducting coating) demonstrate electric conductivity both along the surface and between surfaces. It was demonstrated that the deposition of conducting coatings leads to an increase in the water wettability of the composites compared with pronounced hydrophobic supports. The composites are characterized by good adhesion between components due to a relief film surface as well as high mechanical strength and elasticity provided by the oriented character of the supports.

Copper and palladium bimetallic sub-nanoparticles were stabilized on modified polyaniline materials as an efficient catalyst to promote C-C coupling reactions in aqueous solution

The modified polyaniline self-stabilizing Cu/Pd bimetallic sub-nanocluster Composite materials (Cu/Pd@Mod-PANI-3OH) are obtained through three steps of oxidative polymerization, structural modification, and metal self-trapping. Palladium and copper are confined and coordinated...

Electromagnetic interference shielding study in microwave and NIR regions by highly efficient Ag/ZnS and polyaniline-Ag/ZnS particles

The chemical oxidative polymerization and co-precipitation methods were employed for the preparations of polyaniline (PANI) and silver-doped zinc sulfide (ZnS) nanoparticles to be used for electromagnetic interference (EMI) shielding. PVC-based composite films were fabricated by the incorporation of Ag/ZnS and PANI-Ag/ZnS nanoparticles. These nanoparticles were first analyzed by X-ray diffraction and zetasizer for their crystal structure and particle size. Prepared nanocomposite films were then analyzed for various properties like electrical conductivity, transmission in the near-infrared region (700 nm to 2500 nm), and EMI shielding efficiency in the microwave region (0.1 GHz to 20 GHz). These parameters were characterized by DC Conductivity, NIR spectroscopy, and vector network analyzer. It was found that with the addition of the concentration of nanoparticles, both values of conductivity and shielding efficiency improved. The highest attenuation value in 0.1 to 20 GHz reached 52.5 dB in 0.1 to 20 GHz frequency for 20 wt% PANI-Ag/ZnS and < 0.5% transmission was evaluated in the NIR region.

Chemical Oxidative Condensation of Benzidine in Non-Aqueous Medium: Synthesis and Investigation of Oligomers and Polymer with Benzidine Diimine Units

The oxidative condensation of benzidine has been carried out in acetic acid media using potassium peroxydisulfate as the oxidizing agent. Using different monomer–oxidant molar ratios, benzidine dimer, trimer, and polymer have been synthesized for the first time. It was established that the polybenzidine structure is composed from a sequence of benzidinediimine and diphenylene units with amino/amino end groups and thus proves the possibility of ammonia elimination during the oxidative polymerization of aromatic diamines. The method seems to be common for the synthesis of polymers with the sequence of aromatic diimine and arylene units. TGA analysis of the obtained trimer and polymer was investigated, and the high thermostability of both the polymer and trimer was revealed. According to the obtained data, both polymer and trimer matrix decomposition started at 300 °C, and at 600 °C, 75.94% and of 69.40% of the initial weight remained, correspondingly. Conductivities of the polymer and trimer show a semiconductor-type change from temperature and after doping show an increase in conductivity up to 10−4 Sm/cm.

Fabrication of Methylene Blue Loaded Ovalbumin/Polypyrrole Nanoparticles for Enhanced Phototherapy-Triggered Antitumor Immune Activation

Phototherapy-triggered immunogenic cell death (ICD) hardly elicit robust antitumor immune response partially due to low antigen exposure and inefficient antigen presentation. To address these issues, we developed a novel methylene blue loaded ovalbumin/ polypyrrole nanoparticles (MB@OVA/PPY NPs) via oxidative polymerization and π-π stacking reaction. The as-prepared MB@OVA/PPY NPs with outstanding photothermal conversion efficiency (38%) and photodynamic property could be readily internalized into cytoplasm and accumulated in lysosome and mitochondria. Upon 808 nm and 660 nm laser irradiation, the MB@OVA/PPY NPs not only ablated the tumor cells by inducing local hyperthermia, but also damaged residual tumor cells by generating a large amount of reactive oxygen species (ROS), finally triggered the release of large amount of damage associated molecular patterns (DAMPs). Moreover, the MB@OVA/PPY NPs synergized with DAMPs promoted thematuration and improved antigen presentation ability of DCs in virto and vivo. This work demonstrated that the MB@OVA/PPY NPs could be used as effective nanotherapeutic agents for eliminating the solid tumor and triggering powerful antitumor immune response.

A Facile Method to Synthesize 3D Pomegranate-like Polydopamine Microspheres

Nanospheres have found versatile applications in the biomedical field; however, their possible harmful effects on immune and inflammatory systems are also a crucial concern. Inspired by a pomegranate structure, we demonstrated a novel structure for the nanostructured microspheres to overcome the drawbacks of nanospheres without compromising their merits. In this study, 3D pomegranate-like polydopamine microspheres (PDAMS) were synthesized by self-oxidative polymerization of dopamine hydrochloride. Herein, controlling the pH during polymerization led to synthesizing homogeneous agglomerated nano-sized spheres (400–2000 nm) and finally forming tunable and monodisperse micron-sized particles (21 µm) with uniform spherical shape porous microstructure. PDAMS interaction with the potential targets, Bone morphogenetic protein-2 (BMP2), Decorin, and Matrilin-1, was investigated via molecular calculations. Theoretical energy analysis revealed that PDAMS interaction with BMP2, Decorin, and Matrilin-1 is spontaneous, so that a protein layer formation on the PDAMS surface suggests application in bone and cartilage repair. It was also observed that PDAMS presented in-vitro degradation within 4 weeks. Here, disappearance of the UV-VIS spectrum peak at 280 nm is accompanied by the degradation of catechol groups. Pomegranate-like PDAMS support the biomimetic formation of hydroxyapatite-like layers, making them appropriate candidates for hard tissue applications. Herein, the appearance of peaks in XRD spectrum at 31.37, 39.57, 45.21, and 50.13° attributed to hydroxyapatite-like layers formation. All these results demonstrated that self-oxidative polymerization under a controllable pH can be a green and straightforward technique for preparing the pomegranate-like PDAMS and providing an innovative basis for further pre-clinical and clinical investigations.

Preparation and Characterization of a Novel Activated Carbon@Polyindole Composite for the Effective Removal of Ionic Dye from Water

The present study is aimed at the synthesis and exploring the efficiency of a novel activated carbon incorporated polyindole (AC@PIN) composite for adsorptive removal of Malachite Green (MG) dye from aqueous solution. An AC@PIN hybrid material was prepared by in situ chemical oxidative polymerization. The physico-chemical characteristics of the AC@PIN composite were assessed using Fourier-transform infrared spectrometer, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, ultraviolet visible spectroscopy, and determination of point of zero charge (pHPZC). A series of adsorption studies was conducted to evaluate the influence of operational parameters such as pH, contact time, initial dye concentration, AC@PIN dosage, and temperature on dye adsorption behavior of developed composite. A maximum dye removal percentage (97.3%) was achieved at the pH = 10, AC@PIN dosage = 6.0 mg, initial dye concentration 150 mg L−1, and temperature = 20 °C. The kinetic studies demonstrated that the adsorption of MG on AC@PIN followed pseudo-second-order model (R2 ≥ 0.99). Meanwhile, Langmuir isotherm model was founded to be the best isotherm model to describe the adsorption process. Finally, the recyclability test revealed that the composite exhibits good recycle efficiency and is stable after 5 cycles. The obtained results suggest that AC@PIN composite could be a potential candidate for the removal of MG from wastewater.