Studies on Polybenzimidazole and Methanesulfonate Protic-Ionic-Liquids-Based Composite Polymer Electrolyte Membranes

Funding Information: This project was funded by the National Plan for Science, Technology and Innovation (MAARIFAH), King Abdulaziz City for Science and Technology, Kingdom of Saudi Arabia, Award Number (2-17-01-001-0042). Publisher Copyright: © 2023 by the authors.In the present work, different methanesulfonate-based protic ionic liquids (PILs) were synthesized and their structural characterization was performed using FTIR, 1H, and 13C NMR spectroscopy. Their thermal behavior and stability were studied using DSC and TGA, respectively, and EIS was used to study the ionic conductivity of these PILs. The PIL, which was diethanolammonium-methanesulfonate-based due to its compatibility with polybenzimidazole (PBI) to form composite membranes, was used to prepare proton-conducting polymer electrolyte membranes (PEMs) for prospective high-temperature fuel cell application. The prepared PEMs were further characterized using FTIR, DSC, TGA, SEM, and EIS. The FTIR results indicated good interaction among the PEM components and the DSC results suggested good miscibility and a plasticizing effect of the incorporated PIL in the PBI polymer matrix. All the PEMs showed good thermal stability and good proton conductivity for prospective high-temperature fuel cell application.publishersversionpublishe

Characterization of Thermal, Ionic Conductivity and Electrochemical Properties of Some p-Tosylate Anions-Based Protic Ionic Compounds

Kingdom of Saudi Arabia, Award Number (2-17-01-001-0042In the present work, six protic ionic liquid (PIL) compounds based on p-toluene sulfonic acid [PTSA] anion along with different cations viz. tetraethylenepentammonium [TEPA], triethy-lammonium [TEA], pyridinium [Py], N-methylpiperidinium [Pip], 1-methylimidazolium [Im], and N-methylpyrrolidinium [Pyrr] were synthesized using the standard neutralization reaction method. The structural characterization of these compounds was achieved using FTIR,1H and13C NMR spectroscopies. Thermal behavior was studied using differential scanning calorimetry to determine the melting point (Tm) and crystallization (Tc ) temperatures. Thermogravimetric analysis was carried out to determine the thermal stability and degradation temperatures (Tdec) and to ascertain the hygroscopic or hydrophobic nature of the synthesized compounds. Structural effects on the outcome of various properties were witnessed and discussed in detail. Electrochemical impedance spectroscopy was utilized to study the electrical transport properties of the PILs at different temperatures. Cyclic voltammetry was performed to analyze the electrochemical stability of these PILs. Low values of activation energy indicating easy proton transportation along with good electrochemical stability make the PILs a potential candidate for use in the preparation of polymer electrolytes membranes for fuel cell applications.publishersversionpublishe

Mechanical, thermal and morphological studies of microfibrillated jute/PLA biocomposites

In the present study, biocomposites based on microfibrillated jute (MFJ) fibre and polylactic acid (PLA) have been prepared by solvent-assisted compression moulding techniques. The MFJ is obtained by a sequence of alkali, chlorite and acid treatments of jute fibre. The biocomposites are fabricated by loading of 10, 20 and 30 wt% of MFJ fibre into the PLA matrix. The effect of MFJ fibre loading on the mechanical, thermal, and morphological properties of the composites is also studied. Among these composites, it is observed that 10 wt% fibre-filled biocomposite shows improved tensile strength andtensile modulus compared to virgin PLA film. Similarly, storage modulus and loss modulus are also found improved for the composites. These composites exhibit higher water absorption capacity and lower thermal stability than virgin PLA. The fibre-matrix adhesion is evaluated by scanning electron microscopy. The results are attributed to the improved interfacial adhesion between MFJ and PLA matrix for 10 wt% fibre-filled biocomposites

Essential Oil-Containing Polysaccharide-Based Edible Films and Coatings for Food Security Applications

The wastage of food products is a major challenge for the food industry. In this regard, the use of edible films and coatings have gained much attention due to their ability to prevent the spoilage of the food products during handling, transport, and storage. This has effectively helped in extending the shelf-life of the food products. Among the various polymers, polysaccharides have been explored to develop edible films and coatings in the last decade. Such polymeric systems have shown great promise in microbial food safety applications. The inclusion of essential oils (EOs) within the polysaccharide matrices has further improved the functional properties of the edible films and coatings. The current review will discuss the different types of polysaccharides, EOs, methods of preparing edible films and coatings, and the characterization methods for the EO-loaded polysaccharide films. The mechanism of the antimicrobial activity of the EOs has also been discussed in brief

Polysaccharide-Based Nanocomposites for Food Packaging Applications

The article presents a review of the literature on the use of polysaccharide bionanocomposites in the context of their potential use as food packaging materials. Composites of this type consist of at least two phases, of which the outer phase is a polysaccharide, and the inner phase (dispersed phase) is an enhancing agent with a particle size of 1–100 nm in at least one dimension. The literature review was carried out using data from the Web of Science database using VosViewer, free software for scientometric analysis. Source analysis concluded that polysaccharides such as chitosan, cellulose, and starch are widely used in food packaging applications, as are reinforcing agents such as silver nanoparticles and cellulose nanostructures (e.g., cellulose nanocrystals and nanocellulose). The addition of reinforcing agents improves the thermal and mechanical stability of the polysaccharide films and nanocomposites. Here we highlighted the nanocomposites containing silver nanoparticles, which exhibited antimicrobial properties. Finally, it can be concluded that polysaccharide-based nanocomposites have sufficient properties to be tested as food packaging materials in a wide spectrum of applications

The Influence of Emulsifiers on the Physiochemical Behavior of Soy Wax/Rice Bran Oil-Based Oleogels and Their Application in Nutraceutical Delivery

This research evaluated the influence of stearic acid, sunflower lecithin, and sorbitan monooleate on soy wax (SYW)/rice bran oil (RBO)-based oleogels. The physiochemical behavior of oleogel samples was evaluated using colorimetry, microscopy, FTIR, mechanical, crystallization kinetics, X-ray diffraction, and a drug release investigation. The prepared oleogels were light yellow, and adding emulsifiers did not change their appearance. All oleogels showed an oil binding capacity of >98%, independent of emulsifier treatment. The surface topography revealed that emulsifiers smoothed the surface of the oleogels. Bright-field and polarized micrographs showed the presence of wax grains and needles. FTIR spectra indicated that oleogel samples had the same functional group diversity as the raw materials. The oleogel samples lacked a hydrogen-bonding peak. Hence, we postulated that non-covalent interactions were involved in the oleogel preparation. According to stress relaxation studies, the firmness and elastic component of oleogels were unaffected by emulsifiers. However, EML3 (oleogel containing sorbitan monooleate) showed lower relaxing characteristics than the others. EML3 exhibited the slowest crystallization profile. Due to its low d-spacing, EML3 was found to have densely packed crystal molecules and the largest crystallite size. The in vitro drug release studies showed that emulsifier-containing oleogels dramatically affected curcumin release. These results may help customize oleogels properties to adjust bioactive component release in the food and pharmaceutical industries

An Insight on the Swelling, Viscoelastic, Electrical, and Drug Release Properties of Gelatin–Carboxymethyl Chitosan Hydrogels

<p>The present study reports the in-depth analysis of the gelatin–carboxymethyl chitosan hydrogels. The composite system formed phase-separated hydrogels, which is confirmed by scanning electron microscopy. The swelling of the carboxymethyl chitosan-containing hydrogels was lower than the gelatin hydrogel. Macroscale deformation study using a static mechanical tester indicated a viscoelastic nature of the hydrogels. A decrease in the impedance of the hydrogels was observed with an increase in the carboxymethyl chitosan content. The drug release from the hydrogels was predominantly Fickian diffusion mediated and was released in its active form. The results suggested the potential use of the hydrogels as drug delivery matrices.</p

Conductive Plastics from Al Platelets in a PBT-PET Polyester Blend Having Co-Continuous Morphology

Conductive plastics are made by placing conductive fillers in polymer matrices. It is known that a conductive filler in a binary polymer blend with a co-continuous morphology is more effective than in a single polymer, because it aids the formation of a &lsquo;segregated conductive network&rsquo;. We embedded a relatively low-cost conductive filler, aluminium nano platelets, in a 60/40 PBT/PET polymer blend. While 25 vol.% of the Al nanoplatelets when placed in a single polymer (PET) gave a material with the resistivity of an insulator (1014 &Omega;cm), the same Al nano platelets in the 60/40 PBT/PET blend reduced the resistivity to 7.2 &times; 107 &Omega;cm, which is in the category of an electrostatic charge dissipation material. While PET tends to give amorphous articles, the 60/40 PBT/PET blends crystallised in the time scale of the injection moulding and hence the conductive articles had dimensional stability above the Tg of PET

A Convenient and Simple Ionic Polymer-Metal Composite (IPMC) Actuator Based on a Platinum-Coated Sulfonated Poly(ether ether ketone)&ndash;Polyaniline Composite Membrane

Herein, we present new approaches for developing sulfonated polyether ether ketone (SPEEK) and polyaniline-based (PANI) actuator formed by film-casting and chemical reduction of Pt electrodes. We have thoroughly studied the synthesis of SPEEK and characterized it by different analytical techniques. The ion-exchange capacity (IEC) and proton conductivity of SPEEK-PANI polymer membrane were calculated to be 1.98 mmol g&minus;1 and 1.97 &times; 10&minus;3 S cm&minus;1, respectively. To develop an IPMC actuator, SPEEK was combined with PANI through in-situ polymerization method. SEM and XRD were used to check the morphology of the given SPEEK-PANI-Pt membrane. In addition, FT-IR and EDX techniques confirmed the molecular structure and chemical conformation of SPEEK-PANI polymer membrane. Pt electrode layers homogeneously dispersed on the IPMC membrane surface, which was demonstrated by smooth SEM micrographs. The actuation functioning, including the high bending deflection, proton conductivity, current density and IEC of IPMC actuator based on SPEEK-PANI-Pt, was obtained owing to its strong electrochemical and electromechanical characteristics. Synergistic combinations of SPEEK and PANI produced membrane that are flexible, mechanically strong and robust. The developed materials have immense capability as actuators for various applications including in biomimetics and robotics