Polyvinyl Alcohol Methylcellulose Research Articles

Silver Nanoparticles Incorporated PVA‐MC Blends: A Systematic Approach To Understand Its Properties For Food Packaging Applications

AbstractHither‐to‐unknown one‐pot method for the synthesis and stabilization of silver nanoparticles (AgNPs) from silver nitrate (AgNO3) through uncross‐linked and cross‐linked polyvinyl alcohol/methyl cellulose (PVA/MC) blend using solution casting method is discussed in detail. The formed films were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy dispersive X‐ray spectroscopy (SEM‐EDX), transmission electron microscopy (TEM) and analyzed for its physical, mechanical, biodegradable and antibacterial properties (particle size, water vapour transmission rate, water contact angle, thermogravimetric analysis (TGA), UV‐Vis spectroscopy and migration). SEM and TEM results indicated that the formation of silver nanoparticles are spherical in shape as well as nano in size. FTIR spectroscopic analysis indicates the existence of hydrogen bonds in cross‐linked blend and complex of silver (Ag) in uncross‐linked blend. Further, enhanced mechanical, water barrier, and thermal properties are observed for the films containing AgNPs. Antibacterial test by disc diffusion method showed that, uncross‐linked and cross‐linked blend with AgNPs have more inhibition (mm) against L. Monocytogenes (10.33), Klebsiella (9.67) (Gram‐positive) and Salmonella (9.33), E. Coli (8.33) (Gram‐negative) strains respectively. Migration studies demonstrated that the developed films could be suitable for fatty food packaging.

Studies of Circuit Design, Structural, Relaxation and Potential Stability of Polymer Blend Electrolyte Membranes Based on PVA:MC Impregnated with NH4I Salt.

This work presents the fabrication of polymer electrolyte membranes (PEMs) that are made of polyvinyl alcohol-methylcellulose (PVA-MC) doped with various amounts of ammonium iodide (NH4I). The structural and electrical properties of the polymer blend electrolyte were performed via the acquisition of Fourier Transform Infrared (FTIR) and electrical impedance spectroscopy (EIS), respectively. The interaction among the components of the electrolyte was confirmed via the FTIR approach. Electrical impedance spectroscopy (EIS) showed that the whole conductivity of complexes of PVA-MC was increased beyond the addition of NH4I. The application of EEC modeling on experimental data of EIS was helpful to calculate the ion transport parameters and detect the circuit elements of the films. The sample containing 40 wt.% of NH4I salt exhibited maximum ionic conductivity (7.01 × 10−8) S cm−1 at room temperature. The conductivity behaviors were further emphasized from the dielectric study. The dielectric constant, ε’ and loss, ε’’ values were recorded at high values within the low-frequency region. The peak appearance of the dielectric relaxation analysis verified the non-Debye type of relaxation mechanism was clarified via the peak appearance of the dielectric relaxation. For further confirmation, the transference number measurement (TNM) of the PVA-MC-NH4I electrolyte was analyzed in which ions were primarily entities for the charge transfer process. The linear sweep voltammetry (LSV) shows a relatively electrochemically stable electrolyte where the voltage was swept linearly up to 1.6 V. Finally, the sample with maximum conductivity, ion dominance of tion and relatively wide breakdown voltage were found to be 0.88 and 1.6 V, respectively. As the ions are the majority charge carrier, this polymer electrolyte could be considered as a promising candidate to be used in electrochemical energy storage devices for example electrochemical double-layer capacitor (EDLC) device.

An Investigation into the PVA:MC:NH4Cl-Based Proton-Conducting Polymer-Blend Electrolytes for Electrochemical Double Layer Capacitor (EDLC) Device Application: The FTIR, Circuit Design and Electrochemical Studies.

In this report, the preparation of solid polymer electrolytes (SPEs) is performed from polyvinyl alcohol, methyl cellulose (PVA-MC), and ammonium chloride (NH4Cl) using solution casting methodology for its use in electrical double layer capacitors (EDLCs). The characterizations of the prepared electrolyte are conducted using a variety of techniques, including Fourier transform infrared spectroscopy (FTIR), electrical impedance spectroscopy (EIS), cyclic voltammetry (CV), and linear sweep voltammetry (LSV). The interaction between the polymers and NH4Cl salt are assured via FTIR. EIS confirms the possibility of obtaining a reasonably high conductance of the electrolyte of 1.99 × 10−3 S/cm at room temperature. The dielectric response technique is applied to determine the extent of the ion dissociation of the NH4Cl in the PVA-MC-NH4Cl systems. The appearance of a peak in the imaginary part of the modulus study recognizes the contribution of chain dynamics and ion mobility. Transference number measurement (TNM) is specified and is found to be (tion) = 0.933 for the uppermost conducting sample. This verifies that ions are the predominant charge carriers. From the LSV study, 1.4 V are recorded for the relatively high-conducting sample. The CV curve response is far from the rectangular shape. The maximum specific capacitance of 20.6 F/g is recorded at 10 mV/s.

Characterization and drug delivery properties of gamma irradiated poly (vinyl alcohol)/methylcellulose (PVA/MC) blends

Characterization and drug delivery properties of gamma irradiated poly (vinyl alcohol)/methylcellulose (PVA/MC) blends

Kinetic studies on the thermal decomposition of gamma-irradiated poly(vinyl alcohol (PVA)/methyl cellulose (MC) blends

Poly(vinyl alcohol)/ methyl cellulose (PVA/MC) blends, at different ratios were prepared into films by solution casting using, water as a common solvent, and gamma irradiated at various doses. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to study the thermal properties of gamma irradiated PVA/MC blends. It is expected that these methods would enable to understand the effect of gamma irradiation on the mechanism of thermal decomposition. The kinetic parameters such as energy of activation (Ea) and regression r2 for the thermal decomposition were determined by three different methods. In the present work, the Coats-Redfern, Broido and Horowitz-Metzger methods were applied. The results indicated that the Ea and r2 values of the gamma irradiated PVA/MC blends as determined by the three methods were comparable.