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Magnetite nanoparticles (Fe₃O₄ NPs) are prepared using chemical reduction method. This is a simple, economical, nontoxic, facile, clean, and environment friendly process. Preparation of composite polymeric membrane of polyvinyl alcohol (PVA)/Fe₃O₄ has been performed using dry phase inversion technique for different medical/filtration applications. PVA coatings using magnetite NPs are focused to passivate the surface and decrease agglomeration and also reduce module biomedical absorption and most of the times increase dispersion stability. Therefore, research on PVA coatings on magnetite NPs are in trend now a days, as they are of high charge density that makes them stable in dispersion by electrostatic repulsion. The prepared samples (Fe₃O₄ NPs) and PVA/Fe₃O₄ composite membrane have been analyzed for their different properties by using X-ray direction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–Vis) and thermogravimetric Analysis (TGA).

Complex three-dimensional (3D) porous scaffolds with macro-pore size of 400–800 μm based on polyvinyl alcohol (PVA) powder were successfully developed by selective laser sintering (SLS) technology. The PVA scaffolds had customizable shape, controlled and totally interconnected porous structure, and high porosity. The microstructure and mechanical property were performed for their suitability for tissue engineering (TE). The results showed that PVA did not decompose while the degree of crystallization decreased in a given sintering condition. Moreover, there were micro-pores with sizes of 20–100 μm in the scaffold. The actual porosity of sintered scaffolds could be up to 82.35%, which was higher than the value of the designed models. An in vitro biocompatibility test showed MG-63 cells could well spread on the scaffold surface. The presented work demonstrates the favorable potential of PVA powder as TE scaffolds fabricated via SLS.

Composites of polyvinyl alcohol (PVA) containing silver nanoparticles were prepared using in situ synthesis of nanoparticles. Structure and properties of these composites were investigated using UV-Vis spectroscopy, XRD, DSC, SEM and AFM. The studies show that PVA can reduce the AgNO₃ to yield silver nanoparticles and in the process forms bonds with PVA chains. The anti-bacterial properties of these films were studied by qualitative as well as quantitative methods which gave the values of 98% for gram positive and 89% for gram negative bacteria.

This report discusses in detail about the Fire retardant (FR) characteristics of polyvinyl alcohol (PVA) matrix fabricated by impregnating zinc borate nanoparticles (ZB Nps) as FR with trace amounts of copper chloride/aluminum chloride by solvent casting method. ZB Nps prepared by co-precipitation method are characterized using XRD, FTIR, SEM, TEM, etc. XRD pattern revealed the crystal geometry of ZB Nps and SEM and TEM micrographs depict a rod-like structure with 300–400nm size. Appropriate amount of ZB Nps and transition metal salts are mixed with PVA in aqueous medium and thin film samples are obtained by solvent casting method. The vibrational spectra, thermal stability and flammability of the polymeric composites are characterized using FTIR, TG/DTA and Flammability tester, respectively. FTIR spectra confirm the existence of ZB Nps in the prepared polymer composites. TG/DTA studies revealed higher degradation temperature and thermal stability of polymer composite over pure PVA. The limiting oxygen index (LOI) test presented a convincing account about the improved FR nature of obtained polymer nano composite with a significant LOI of 56% compared to virgin polymer which have LOI of 19.6%.

Polyvinyl alcohol (PVA) was grafted on graphene nanosheets (GN) in the reduction of graphene oxide with hydrazine hydrate. The obtained GN-PVA (GP) suspension was treated with the freezing–thawing cycle to fabricate 3D porous monolithic GP materials, which were modified with carbon disulfide to introduce xanthan groups on the wall of porous materials, marked as GPCs. The characterization of GPCs confirmed that PVA was attached on the surface of GNs, and xanthan groups were effectively functionalized on the porous structures, which were composed of randomly oriented GNs. The Pb${}^{2+}$ adsorption pattern for GPC materials was investigated. The kinetic adsorption and isotherm data fit the pseudo second-order kinetic and the Langmuir isotherm models, respectively. The maximum adsorption capacity of Pb${}^{2+}$ reached 242.7mg/g. And GPCs for Pb${}^{2+}$ adsorption could be regenerated with ethylenediamine tetracetic acid (EDTA) solution for repetitious adsorption.

Green-emitting Mn${}^{2+}$ -doped zinc silicate nanophosphor was synthesized by solvothermal method with the assistance of polyvinyl alcohol (PVA). The structure, morphology and optical properties of phosphors were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR) and Photoluminescence Spectroscopy (PL). Also, the application of Mn${}^{2+}$ -doped zinc silicate phosphor in electronic devices was studied. Furthermore, Zn₂SiO₄: Mn${}^{2+}$ phosphor was used to be a fluorescent sensor for the first time to detect inorganic ions and small molecules. The results indicated that pure $\alpha$-Zn₂SiO₄ phase nanoparticles with spherical morphology were obtained. The results also showed that the phosphor has excellent selectivity and sensitivity for detecting Cr${}^{3+}$ ions, Cr₂O₇${}^{2-}$ ions and 4-nitrophenol (4-NP) with low detection limits (Cr${}^{3+}$ ions: 1.34 $\mu$M, Cr₂O₇${}^{2-}$ ions: 5.86 $\mu$M, 4-NP: 2.38 $\mu$M). Thus, Mn${}^{2+}$ -doped zinc silicate manganese phosphor has potential applications in light-emitting diodes (LEDs) and fluorescent sensors.

Present study is carried out to understand the effect of conducting polymer, polypyrrole (PPy) on structural, morphological, thermal and dielectric properties of bio-compatible polymer blend film of polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP). The growth of PPy in the matrix of PVA–PVP was analyzed using XRD, FT-IR and SEM studies. The shifting in positions and broadening of XRD diffraction peaks of PVA–PVP-PPy from that of PVA–PVP indicates the structural modification and reduction in the crystallinity of the PVA–PVP due to incorporation of PPy. The SEM studies suggest scattered growth of PPy in PVA–PVP matrix at lower concentration of pyrrole monomer. As the monomer concentration is increased, the uniform and interconnected growth of PPy was observed in SEM micrographs. The TGA thermograms show faster thermal degradation of PVA–PVP- PPy films at lower temperature as compared to PVA–PVP films. The blend films of PVA–PVP- PPy exhibited enhanced values of dielectric constant and ac conductivity as compared to the virgin blend film which are observed to increase with increasing concentration of PPy. The high dielectric constant with high ac conductivity exhibited by PVA–PVP-PPy film suggests its possible application as flexible dielectric material for the development of biosensors, energy storage devices in field of green organic electronics.

Polyethylene glycol (PEG) has been grafted onto surface of many medical devices to reduce or eliminate protein adsorption that often leads to infection or inflammatory responses. Besides commonly used surface activation strategies, here in this work, the novel functional brush copolymer poly (vinyl alcohol)-g-PEG-co-polyurethane (PVA-g-(PEG-co-PU)) was first synthesized, characterized, and evaluated. PVA is used here as a versatile backbone platform for grafting functional molecules. On the one hand, the PU molecules can attach to the surface of desired PU-based implants, on the other hand, the presence of densely grafted PEG at the materials–tissue interface effectively impedes nonspecific protein adsorption. These copolymers with various grafting ratio of PEG and PU were analyzed by Fourier transform infrared spectroscopy and gel permeation chromatography. The brush copolymers that were obtained were further coated on the PU surface and contact angle measurements were performed. It was found that the brush copolymers turn the surface more hydrophilic with increasing PEG grafting density. Furthermore, the effects of PEG ratio on protein adsorption-resistant behavior were investigated. Protein adsorption was found to be the lowest on the surfaces with the highest PEG grafting density on PVA backbone. The study demonstrated unique brush copolymer to work as a potentially useful coating material.

Monolithic PVA-doped silica gels were prepared by the sol-gel process and dehydrated by conventional freeze-drying. Tetraethoxysilane (TEOS), tert-butanol (TBA) and distilled-deionized (DDI) water were used as major materials in hydrolysis of the silica gels under acid-catalyzed conditions. Characteristics of PVA-doped silica gels were evaluated by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and nitrogen adsorption-desorption analysis (BET) methods, respectively. The FT-IR patterns show that a typical feature of Si-O-Si linkages is formed. Morphological analysis by SEM indicates that a typical porous gel structure is achieved through freeze drying, and the PVA-doped silica gel has an interconnected porous structure with a pore size of 1-10 μm at macropore scale. Characterization by BET shows that the PVA-doped silica gels are mesoporous materials with a specific surface area of 1167 m²/g, a pore specific volume of 1.548 cm³/g, and an average pore size of 2.653 nm.

Green-emitting Mn²⁺-doped zinc silicate nanophosphor was synthesized by solvothermal method with the assistance of polyvinyl alcohol (PVA). The structure, morphology and optical properties of phosphors were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR) and Photoluminescence Spectroscopy (PL). Also, the application of Mn²⁺-doped zinc silicate phosphor in electronic devices was studied. Furthermore, Zn₂SiO₄: Mn²⁺ phosphor was used to be a fluorescent sensor for the first time to detect inorganic ions and small molecules. The results indicated that pure α-Zn₂SiO₄ phase nanoparticles with spherical morphology were obtained. The results also showed that the phosphor has excellent selectivity and sensitivity for detecting Cr³⁺ ions, Cr₂O₇²⁻ ions and 4-nitrophenol (4-NP) with low detection limits (Cr³⁺ ions: 1.34 μM, Cr₂O₇²⁻ ions: 5.86 μM, 4-NP: 2.38 μM). Thus, Mn²⁺-doped zinc silicate manganese phosphor has potential applications in light-emitting diodes (LEDs) and fluorescent sensors.