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• Simulations using molecular dynamics and Monte Carlo were conducted to determine the membranes' gas transport characteristics. • An analysis of the morphological properties such as mechanical properties, cohesive energy density (CED), end-to-end distance, and solubility parameter (δ) of membranes has been conducted. • Various calculation modes were used in the MS software, including Sorption, Forcite, NVT, NPT, and Compass III. Our study employed Molecular dynamics (MD) simulations using BIOVIA Materials Studio 2021 software programs to analyze neat and mixed matrix membranes (MMMs) for their solubility behaviour, thermodynamics, mechanical properties, and separation properties. The d -space, followed by the Matrimid 5218 (MAT) membranes' amorphous state, was enhanced by adding particles to their structure. Furthermore, Calix[4]arene (CA) particles lead to improved membrane physicochemical properties, such as fractional free volume (FFV), glass transition temperature (Tg), Young's Modulus (E), shear modulus (G), and bulk modulus (B), which are indicators of improved thermal resistance and transport capacity. Besides, the N 2 , CH 4 , and CO 2 gases' transport properties and performance of membrane structures were analyzed in terms of their diffusivity, solubility, permeability, and selective behaviours. Based on MC simulations, increasing pressure results in a significant increase in gas adsorption, and CO 2 is more readily absorbed than N 2 or CH 4 , thanks to the robust interaction between the CO 2 molecule and membrane structures. There were significant improvements in the CO 2 permeability of MMMs filled with 0.75% CA particles compared to the neat MAT. Moreover, the MMMs were found to have improved selectivity in CO 2 /N 2 and CO 2 /CH 4 in comparison with neat membranes. Lastly, the measuring results of transport properties indicated that the MAT-CA (0.75%) membrane is proper for industrial applications, including the treatment of natural gas. [Display omitted] [ABSTRACT FROM AUTHOR]

Crosslinked network polymers have numerous important applications in engineering, biomedicine, and the environment. Establishing a crosslinked polymer network is an essential initial step toward studying the structure and function of polymer membranes. In this study, we developed a Python script named PXLink that integrates with GROMACS software to simulate the crosslinked aromatic polyamide (PA) membrane, which is widely used in desalination and water treatment. PXLink can create chemical bonds between the neighboring carboxyl and amine groups and relax the system during the crosslinking, utilizing energy minimization and molecular dynamics simulations implemented in GROMACS. The accuracy of our protocol has been successfully validated through a benchmark study of water diffusivity and the structural properties of a solvated membrane, including pore size distribution, membrane density, and the stacking of aromatic benzene rings (density profile and ordering). Moreover, the comparison between the dry and wet polymer membranes reveals that the swelling of the membrane surface leads to the expansion of subnanopores and the increased ordering of local structures. After the swelling of the membrane, the number of pores with a radius around the main region of 0.2 nm decreases, while more pores in the range of 0.22–0.38 nm are observed. There is also an increase in the orderliness of local structures, as evidenced by the increasing order parameter of aromatic ring pairs with a distance ranging from 0.7 to 0.8 nm. Our developed script will be a valuable tool for designing and discovering crosslinked polymers. Program Title: PXLink CPC Library link to program files: https://doi.org/10.17632/yjw2ghfzmh.1 Developer's repository link: https://github.com/zchinet30/PXLink Licensing provisions: GNU General Public License 3 Programming language: Python Nature of problem: The formation of a crosslinked polymer network is essential for theoretical studies and numerous practical applications. However, simulating the polymer crosslinking process using conventional molecular dynamic simulations presents challenges due to its intricate nature, which involves a complex interplay of physical processes and chemical reactions within a large-scale system. Solution method: To address this limitation, we developed PXLink, a python-based script, which integrates with the molecular dynamics software of GROMACS for the simulation of polymer crosslinking. [ABSTRACT FROM AUTHOR]

The article reports on a study, by Linsen Yang at the Chinese Academy of Sciences in Beijing, China and his colleagues, published in the journal "Nature Sustainability," which has created a polymer membrane inspired by the fractal-like nature of blood vessels which can absorb 20 times more uranium from seawater than previous approaches.

Purpose: Efficient numerical assessment of performance is particularly important in digital material design of porous materials. This study aims to present an up-scaled approach to virtually investigate permeation of fluids through a real porous filter membrane with a heterogeneous micro-structure. Design/methodology/approach: The method of asymptotic homogenization is applied. The structural parameters of the micro-structure are directly obtained from structural equation modeling image analysis of a commercial filter membrane without fitting procedures. The simulation results are compared to permeation experiments of gaseous nitrogen and liquid water. Findings: The authors found that variations in the pressure gradients across the membrane, resulting from the heterogeneity of pore structure, need to be considered. Remarkable agreement between simulations and experiments is observed. Originality/value: Despite some research in the field of filtration, no studies on filter membranes have been published yet, although they represent a large segment of filtration technology. [ABSTRACT FROM AUTHOR]

The article reports on updates in lithium production, particularly the developments of new methods to extract lithium from brine. Other topics include the high demand for lithium used for making batteries, the high lithium resources in Argentina, Bolivia and Chile, and the polymer membrane designed by Benny Freeman of University of Texas and to be used by EnergyX to extract lithium.

A coupled theory accounting for fluid diffusion and large deformations of elastic-viscoplastic microporous polymeric materials is presented. The theory is intended to represent the coupled deformation–diffusion response of a material which at a microscopic scale consists of a porous polymeric skeleton and a freely moving fluid in a fully connected pore space. Potential applications of the theory include modeling the response of polymer microfiltration membranes, as well as modeling the response of several hydrated biological tissues which are microporous polymeric materials containing a high concentration of liquids. [ABSTRACT FROM AUTHOR]

• Analytical model for the drug delivery time considering flexural, fluidic, and geometrical parameters in injectable microsystems. • Design and optimization guidelines using concise non-dimensional formulae for injectable microsystems. • Concise analytical, but parametric, formulae to determine the pressure-volume relationship of any flexible polymer membrane using the Marlow hyper-elastic model. Injectable bioelectronic devices provide programmable drug volume delivery control via flexible electrochemical pumps featuring scalable designs for localized drug delivery experiments involving small animals and future drug delivery in humans, especially for life saving medication. A model for the drug delivery time is established from the ideal gas law, finite-deformation theory of flexible membrane, and microfluidics of the channel. It identifies two non-dimensional parameters involving the electrochemical, flexural, and microfluidic terms to control the drug delivery process. An analytical solution is derived from the perturbation method, which agrees well with the numerical solution. These results have relevance in design/optimization of bioelectronic devices used in localized delivery studies in small animals and humans where drug delivery time is an important parameter to ensure complete delivery within a required timeframe. [ABSTRACT FROM AUTHOR]

Ionic polymer metal composites (IPMCs) consist of an electroactive polymeric membrane plated with metal electrodes. They hold promise as actuators and sensors for soft robotics and biomedical applications. Their capabilities ensue from the motion, within the membrane, of a fluid phase consisting of ions dispersed in a solvent. Toward a thorough understanding of IPMC multiphysics, we propose a large deformation theory combining electrochemistry and poromechanics. Namely, we modify the theory recently developed by Porfiri's group by introducing the transport of the solvent, whose redistribution determines the volumetric deformation of the fluid-saturated membrane, and we further account for the cross-diffusion of solvent and ions. In actuation, the imposed voltage drop across the electrodes triggers ion migration, such that the solvent is transported toward the cathode by electro-osmosis. This determines the initial bending toward the anode; then, back-relaxation occurs because of both the solvent counter-diffusion and the asymmetric redistribution of ions near the electrodes. In short-circuit sensing, the applied load triggers solvent motion, such that ions are mainly transported toward the cathode by convection with the solvent. This determines charge accumulation; then, ion counter-diffusion leads to a decrease of the charge stored at the electrodes. We demonstrate that these behaviors can be predicted by the proposed theory on the basis of relevant finite element benchmarks. Additionally, our analysis encompasses the assessment of the role of the membrane elastic moduli in the counter-diffusion of solvent and ions in IPMC actuation and sensing. • New electrochemo-poromechanical theory for ionic polymer metal composites (IPMCs). • Finite deformation theory including the cross-diffusion of solvent and mobile ions. • Prediction of counter-diffusions of solvent in actuation and ions in sensing. • Explanation of back-relaxation through both electrostatics and solvent transport. • Assessment of the role of the membrane elastic moduli on IPMC actuation and sensing. [ABSTRACT FROM AUTHOR]

The article offers information on several products including the In/Out video playback device from In/Out, the Hammie Tunnel House dog house from Gyms for Dogs; and a polyvinyl chloride membrane from RenoSys.

The article focuses on study conducted by researchers Cher Hon Lau and colleagues on using polymer membranes as an environmental friendly separation technique for hydrogen recovery and mentions that selective ageing of polymers with intrinsic microporosity (PIMs) reduces nitrogen permeability.