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Polymer matrix composites composed of poly(methyl methacrylate) (PMMA) and MXenes (Ti3C2Tx) are synthesized using direct solution blending and casting techniques. MXenes are a new family of two-dimensional materials. Both optical and conductivity properties of the resulting PMMA-MXene nanocomposite thin films are studied as a function of MXene concentration, for the first time. The resulting thin films are in the micrometer range (8.10–8.80 µm) in thickness. As the concentration of MXenes increases, the PMMA embeds MXenes, causing structural disturbance but without any change in the crystal structure. The MXene thickness in single-layered structure is 15–20 nm. Optical investigations such as UV-Vis absorption, absorption coefficient, extinction coefficient, and band gap have been reported to study the light absorption of nanocomposites. Resistivity measurement associated with electrical conductivity is studied. The relationship between optical responses and electrical conductivity is discussed. When compared to pure PMMA (1 × 10−14 to 1 × 10−13 S m−1), nanocomposites have electrical conductivity that is more than 3,000 times higher. The nanocomposites containing 15 wt% MXenes had the highest conductivity of 1.35 × 10−3 S m−1. Both the conductivity improvement and tunable optical findings accelerate the route of integrating MXenes into polymers to create more promising multifunctional composites for optoelectronic applications such as conductive electrodes, thin film transistors, and logic circuits.

Over the last few decades, steady growth in desalination literature has been observed. However, conducting a quantitative analysis of this literature is still a novelty. This study aimed at carrying out a quantitative analysis of desalination literature published during the last 30 years, using bibliometric and content analysis techniques, based on the Web of Science database. The bibliometric analysis revealed that desalination has received much attention after the year 2000, as 95.4% of literature has been published in two decades after 2000. The text mining analysis showed that the hot themes of desalination research are reverse osmosis optimization, graphene implications, interfacial polymerization, capacitive deionization, carbon nanotube implications, and antifouling techniques. Furthermore, it was observed that many desalination technologies have emerged recently that make it a challenge to choose the right desalination technology for industrialization. Therefore, this study also contributed to identifying the factors that are important for the industrialization of desalination technologies and, based on these identified factors, this study has compared different desalination technologies to unearth the energy-efficient and low production cost technology. Analytical hierarchy process was used for comparing existing desalination technologies based on eight different parameters and it demonstrated that reverse osmosis is the best available technology for desalination.

Given the abundance of functional groups, meso- and macro-pores, and a high surface area, the piperazine-based poly(amic acid) was employed as a heterogeneous catalyst in the multicomponent reaction to prepare pyrrolidinone scaffolds in a green solvent, acting as a medium for mass transfer and crystallization solvent. The important parameters of the reaction were investigated to find the optimal reaction conditions. A conversion of 100% was obtained at reflux conditions within 30–100 min using a catalytic amount of 200 mg of piperazine-based poly(amic acid) per 2 mmol of reactants (100 mg of cat./1 mmol of reactant). The piperazine-based poly(amic acid) exhibited high recyclability and the recovered catalyst could be used in successive runs without worthy loss in its activity. This work revealed the catalytic activity of the piperazine-based poly(amic acid) as a promising functional polymeric heterogeneous catalyst for organic synthesis. [ABSTRACT FROM AUTHOR]