Synthesis of a biodegradable interpenetrating polymer network of Av-cl-poly(AA-ipn-AAm) for malachite green dye removal: kinetics and thermodynamic studies

Highly stretchable anti-freeze hydrogel based on aloe polysaccharides with high ionic conductivity for multifunctional wearable sensors

Conductive hydrogels have limitations such as non-degradability, loss of electrical conductivity at sub-zero temperatures, and single functionality, which limit their applicability as materials for wearable sensors. To overcome these limitations, this study proposes a bio-based hydrogel using aloe polysaccharides as the matrix and degradable polyvinyl alcohol as a reinforcing material. The hydrogel was crosslinked with borax in a glycerol-water binary solvent system, producing good toughness and compressive strength. Furthermore, the hydrogel was developed as a sensor that could detect both small and large deformations with a low detection limit of 1 % and high stretchability of up to 300 %. Moreover, the sensor exhibited excellent frost resistance at temperatures above -50 °C, and the gauge factor of the hydrogel was 2.86 at 20 °C and 2.12 at -20 °C. The Aloe-polysaccharide-based conductive hydrogels also functioned effectively as a wearable sensor; it detected a wide range of humidities (0-98 % relative humidity) and exhibited fast response and recovery times (1.1 and 0.9 s) while detecting normal human breathing. The polysaccharide hydrogel was also temperature sensitive (1.737 % °C-1) and allowed for information sensing during handwriting.

Interpenetrating polymer networks for desalination and water remediation: a comprehensive review of research trends and prospects

Interpenetrating polymer network (IPN) architectures have gained a lot of interest in recent decades, mainly due to their wide range of applications including water treatment and environmental remediation. IPNs are composed of two or more crosslinked polymeric matrices that are physically entangled but not chemically connected. In polymer science, the interpenetrating network structure with its high polymer chain entanglement is commonly used to generate materials with many functional properties, such as mechanical robustness and adaptable structure. In order to remove a targeted pollutant from contaminated water, it is feasible to modify the network architectures to increase the selectivity by choosing the monomer appropriately. This review aims to give a critical overview of the recent design concepts of IPNs and their applications in desalination and water treatment and their future prospects. This article also discusses the inclusion of inorganic nanoparticles into traditional polymeric membrane networks and its advantages. In the first part, the current scenario for desalination, water pollution and conventional desalination technologies along with their challenges is discussed. Subsequently, the main strategies for the synthesis of semi-IPNs and full-IPNs, and their relevant properties in water remediation are presented based on the nature of the networks and mechanism, with an emphasis on the IPN membrane. This review article has thoroughly investigated and critically assessed published works that describe the latest study on developing IPN membranes, hydrogels and composite materials in water purification and desalination. The goal of this critical analysis is to elicit fresh perspectives regarding the application and advantages of IPNs in desalination and water treatment. This article will also provide a glimpse into future areas of research to address the challenges relating to advanced water treatment as well as its emerging sustainable approaches. The study has put forward a convincing justification and establishes the relevance of IPNs being one of the most intriguing and important areas for achieving a sustainable generation of advanced materials that could benefit mankind.

An Interpenetrating Polymer Network Hydrogel Based on Cellulose, Applied to Remove Colorant Traces from the Water Medium: Electrostatic Interactions Analysis

The main objective of this work was the removal of eosin Y and green malachite from an aqueous medium by using a cellulose-based biodegradable interpenetrated network (IPN). The IPN was obtained by the sequenced synthesis method. In the first step, cellulose was crosslinked with epichlorohydrin (ECH). In the second step, the obtained gels were swollen in a reactive mixture solution, which was based on the monomers 2-hydroxyethyl methacrylate (HEMA) and 1,6- hexanediol diacrylate (HDDA). After this, swelling equilibrium was reached through the gels' exposition to UV radiation. An infrared spectroscopy (FTIR) was used to analyze the bond stretching, which confirmed the IPN's formation. The swelling kinetics in aqueous mediums with different pH values showed a high swelling at a basic pH value and a low response in neutral and acidic media. The IPNs showed an improvement in water uptake, compared to the networks based on PHEMA or cellulose. The IPN was used to remove dyes from the water. The results showed that a high percentage of green malachite was removed by the IPN in six minutes of contact time. The experimental results were confirmed by the docking/modeling method of the system (IPN/Dye). The different physical interactions between the IPN and the dyes' molecules were investigated. The interactions of the hydrogen bonds with malachite green were stronger than those with eosin Y, which was in good agreement with the experimental results.

Comparison between removal of Ethidium bromide and eosin by synthesized manganese (II) doped zinc (II) sulphide nanoparticles: kinetic, isotherms and thermodynamic studies

The present work seeks to investigate the kinetics and thermodynamic studies of ethidium bromide (EtBr) and eosin adsorption onto the synthesized Manganese (II) doped Zinc (II) Sulphide nanoparticles. A convenient scheme of co-precipitation was used for the synthesis of Manganese (II) doped Zinc (II) Sulphide nanoparticles. The Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) and X-ray diffractogram (XRD) techniques were used for the characterization of synthesized nanoparticles. The adsorption study was undertaken in a systematic manner. Effects of different experimental parameters were studied using batch adsorption method. It was evident from the results that EtBr and eosin removal was inversely proportional to the concentration of initial dye and directly proportional to contact time and adsorbent used. To study the adsorption equilibrium three different isotherm models like Langmuir, Freundlich and Flory-Huggins were used. It was observed that adsorption data synced most successfully with Langmuir isotherm model as compared to Freundlich and Flory-Huggins isotherm model. To fit the investigational statistics, the kinetic models pseudo 1st order, pseudo 2nd order and intra particle diffusion were taken onto consideration. The maximum dye removal of 98.19% and 97.16% for EtBr and eosin, was observed during the synthesis of nanoparticles.