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Rare earth elements (REEs) are crucial for clean energy technologies but are predominantly purified by solvent extraction using strong acids. This work explores two adsorbents with selective chemistry based on lanmodulin-derived peptides. Two membrane adsorber platforms were synthesized: (1) a poly(vinylbenzyl chloride) membrane with a grafted poly(allyl methacrylate) network and (2) a poly(arylene ether sulfone)membrane with allyl pendant groups. Both membrane adsorbers were functionalized with LanM1 peptides via a thiol−ene click reaction. The morphology, surface chemistry, and adsorption of select trivalent lanthanides (La, Ce, Pr, Nd) were characterized in pH 4−5 solutions, mimicking phosphogypsum waste streams. Results from the adsorption experiments indicate that the lanmodulin peptide sequence maintains its ability to bind when it is immobilized on the surface of polymer fibers for some ions. Despite the different adsorbent designs, the measured capacity of both adsorbents is on the same order of magnitude, which may be explained by differences in the surface area of the fibers 

To quantify how the viscosities of silicone oil (SO) and liquid metal (LM) relate to emulsion-formation (LM-in-SO versus SO-in-LM), a process was developed to produce LM pastes with adjustable viscosity... 

Nanocomposites integrate functional nanofillers into viscoelastic matrices for electronics, lightweight structural materials, and tissue engineering. Herein, the effect of methacrylate-functionalized (MA-SiO 2 ) and vinyl-functionalized (V-SiO 2 ) silica nanoparticles on the thermal, mechanical, physical, and morphological characteristics of poly(ethylene glycol) (PEG) nanocomposites was investigated. The gel fraction of V-SiO 2 composites decreases upon addition of 3.8 wt% but increases with further addition (>7.4 wt%) until it reaches a plateau at 10.7 wt%. The MA-SiO 2 induced no significant changes in gel fraction and both V-SiO 2 and MA-SiO 2 nanoparticles had a negligible impact on the nanocomposite glass transition temperature and water absorption. The Young's modulus and ultimate compressive stress increased with increasing nanoparticle concentration for both nanoparticles. Due to the higher crosslink density, MA-SiO 2 composites reached a maximum mechanical stress at a concentration of 7.4 wt%, while V-SiO 2 composites reached a maximum at a concentration of 10.7 wt%. Scanning electron microscopy, transmission electron microscopy, and small-angle X-ray scattering revealed a bimodal size distribution for V-SiO 2 and a monomodal size distribution for MA-SiO 2 . Although aggregates were observed for both nanoparticle surface treatments, V-SiO 2 dispersion was poor while MA-SiO 2 were generally well-dispersed. These findings lay the framework for silica nanofillers in PEG-based nanocomposites for advanced manufacturing applications. 

Abstract Managing water resources has become one of the most pressing concerns of scientists in both academia and industry. Broadening access to nontraditional water feedstocks, such as brackish water, seawater and wastewater, requires a robust pretreatment process to prolong the lifetime and improve the efficiency of reverse osmosis treatment processes. Herein, pretreatment membranes with tunable hydrophilic characteristics and mechanical properties were developed through a facile and scalable technique. Specifically, poly(vinyl alcohol) (PVA) and poly(vinyl chloride) (PVC) were electrospun at various PVA‐to‐PVC mass ratios and then crosslinked with a poly(ethylene glycol) diacid. Fiber diameters and morphologies were characterized using scanning electron microscopy (SEM); Fourier transform infrared spectroscopy and confocal fluorescence microscopy further confirmed the presence of both polymers. Moreover, a rigorous analysis to map the PVA/PVC concentration was established to accurately determine the relative concentrations of the two polymers on the co‐spun mat. The crosslinking reaction noted above tuned the membrane porosity from 500 to 80 nm, as seen using SEM, and the mechanical properties were probed using tensile testing. The data revealed that the PVC content controlled the mechanical strength; moreover, higher PVA contents were expected to increase water permeation by enhancing the hydrophilicity, but the higher degree of crosslinking in these materials actually reduced water permeation. This work introduces a facile, scalable route for the manufacture of pretreatment membranes with tunable porosity, mechanical properties and water permeation behavior. © 2021 Society of Industrial Chemistry.