Porous Poly(Ionic Liquid) Membranes as Efficient and Recyclable Absorbents for Heavy Metal Ions

High-Toughness CO2-Sourced Ionic Polyurea Adhesives

Polyurea (PUa) adhesives are renowned for their exceptional adhesion to diverse substrates even in harsh environments. However, the presence of quadruple bidentate intermolecular hydrogen bonds in the polymer chains creates a trade-off between cohesive energy and interfacial adhesive energy. To overcome this challenge, a series of CO2-sourced ionic PUa adhesives with ultratough adhesion to various substrates are developed. The incorporated ionic segments within the adhesive serve to partially mitigate the intermolecular hydrogen bonding interactions while conferring unique electrostatic interactions, leading to both high cohesive energy and interfacial adhesive energy. The maximum adhesive strength of 10.9 MPa can be attained by ionizing the CO2-sourced PUa using bromopropane and subsequently exchanging the anion with lithium bis(trifluoromethylsulfonyl)imide. Additionally, these ionic PUa adhesives demonstrate several desirable properties such as low-temperature stability (-80 °C), resistance to organic solvents and water, high flame retardancy, antibacterial activity, and UV-fluorescence, thereby expanding their potential applications. This study presents a general and effective approach for designing high-strength adhesives suitable for a wide array of uses.

Recent advances in poly(ionic liquid)s for biomedical application

Poly(ionic liquid)s (PILs) are polymers containing ions in their side-chain or backbone, and the designability and outstanding physicochemical properties of PILs have attracted widespread attention from researchers. PILs have specific characteristics, including negligible vapor pressure, high thermal and chemical stability, non-flammability, and self-assembly capabilities. PILs can be well combined with advanced analytical instruments and technology and have made outstanding contributions to the development of biomedicine aiding in the continuous advancement of science and technology. Here we reviewed the advances of PILs in the biomedical field in the past five years with a focus on applications in proteomics, drug delivery, and development. This paper aims to engage pharmaceutical and biomedical scientists to full understand PILs and accelerate the progress from laboratory research to industrialization.

Poly(ionic liquid)s with superior swelling and enrichment properties in solvents

The molar swelling ratio and enrichment factor of poly(ionic liquid)s were linearly positively correlated with the Hansen solubility parameter of the solvent and the difference between the Hansen solubility parameters of mixed solvents, respectively.

Synthesis of poly(ionic liquid) for trifunctional epoxy resin with simultaneously enhancing the toughness, thermal and dielectric performances

Poly(ionic liquid) (PIL), integrating the characteristics of both polymers and ionic liquid, is synthesized and employed to modify diglycidyl-4,5-epoxy-cyclohexane-1,2-dicarboxylate (TDE-85). With the addition of PIL, the fracture toughness, and thermal and dielectric performances of TDE-85 were discovered to be simultaneously improved, meanwhile the tensile modulus and strength is increased. Upon an optimal loading of 3 wt% PIL, the critical stress intensity factor (K _IC), tensile modulus and strength are raised by 92.9%, 13.3% and 10.7%, respectively. Multi-toughening mechanisms due to spherical domains of PIL formed in TDE-85 during curing are responsible for the improved toughness. Moreover, the dielectric and thermal properties of TDE-85 are also enhanced by adding PIL. With the optimal addition of 5 wt% PIL, the dielectric constant of the composites is enhanced by 62.5%, the glass transition temperature is increased by 16.58 °C and the residual weight of carbon is increased by 59%.

Vinylimidazole coordination modes to Pt and Au metal centers

Reaction conditions affect the coordination modes of vinylimidazole to platinum and gold.

Porous ionic liquid polymer: A reusable adsorbent with broad operating pH range for speciation of nitrate and nitrite

Ionic liquids (ILs) are a class of fluids with unique physicochemical properties employing polymeric substances emerging new materials. Solidification of ILs into porous materials generates porous ionic liquid polymers that combine the unique characteristics of ILs with common porous materials and polymers. In this study, it's the first time the porous ionic liquid polymer was chosen as a sorbent for extraction and speciation of nitrite and nitrate. Porous IL was prepared through polymerization of 1-allyl-3-methylimidazolium bromide monomers in the presence of azobisisobutyronitrile (AIBN) and crosslinking of ethylene glycol dimethyl acrylate (EGDMA). Parameters affecting the adsorbent performance were optimized. Under the optimal conditions, correlation coefficient (R²) was 0.9996 and LOD was 0.1 µg L^-1. This method presented the linearity in the concentration range between 0.1-100 µg L^-1 and the relative standard deviation was 3.2%. Finally, the adsorption behavior of the obtained sorbent for nitrate and nitrite determination in various real samples was evaluated. The result indicates that the porous ionic liquid polymer showed high adsorption capacity (233 mg g^-1). The convenient preparation of the porous ionic liquid material, as well as high adsorption capacity for anionic pollutants predicted its broad application potential in anion removal materials.

Poly (N-vinyl imidazole) gel-filled membrane adsorbers for highly efficient removal of dyes from water

Energy-efficient and time-saving process for recovery of hazardous dyes from wastewater is highly desired in dyeing industry. In this work, poly(N-vinyl imidazole) (PVI) gel-filled membrane adsorbers were developed for highly efficient recovery of dyes through adsorption filtration. The membrane adsorbers were fabricated via dip-coating of Nylon macroporous membranes in PVI solutions followed by quaternization crosslinking with p-xylylene dichloride (XDC). Physicochemical characterizations indicated that PVI gel was successfully filled and fixed inside the Nylon matrix. In optimized conditions. The treating capacity of membrane adsorbers to typical dye sunset yellow (25 ppm of the feed concentration) reached up to 197 mg/g with the removal ratio >99%. Both the treating capacity and the removal ratio were kept steady even when the permeation flux was as high as 1000 L/m² h. The membrane adsorbers developed in this work were able to not only remove anionic dyes from water, but also separate anionic dyes from cationic ones. The zeta potential and adsorption tests showed that the electrostatic interaction between PVI gel and dye molecules was responsible for the high removal efficiencies to anionic dyes. The membrane adsorbers can be regenerated effectively with NaOH solution and demonstrated good stability in both acidic and alkaline conditions.

Porous Polyelectrolytes: The Interplay of Charge and Pores for New Functionalities

The past decade has witnessed rapid advances in porous polyelectrolytes and there is tremendous interest in their synthesis as well as their applications in environmental, energy, biomedicine, and catalysis technologies. Research on porous polyelectrolytes is motivated by the flexible choice of functional organic groups and processing technologies as well as the synergy of the charge and pores spanning length scales from individual polyelectrolyte backbones to their nano-/micro-superstructures. This Review surveys recent progress in porous polyelectrolytes including membranes, particles, scaffolds, and high surface area powders/resins as well as their derivatives. The focus is the interplay between surface chemistry, Columbic interaction, and pore confinement that defines new chemistry and physics in such materials for applications in energy conversion, molecular separation, water purification, sensing/actuation, catalysis, tissue engineering, and nanomedicine.

Polypropylene Nonwoven Fabric@Poly(ionic liquid)s for Switchable Oil/Water Separation, Dye Absorption, and Antibacterial Applications

Pollutants in wastewater include oils, dyes, and bacteria, making wastewater cleanup difficult. Multifunctional wastewater treatment media consisting of poly(ionic liquid)-grafted polypropylene (PP) nonwoven fabrics (PP@PIL) are prepared by a simple and scalable surface-grafting process. The fabricated PP@PIL fabrics exhibit impressive switchable oil/water separation (η>99 %) and dye absorption performance (q=410 mg g^-1 ), as well as high antibacterial properties. The oil/water separation can be easily switched by anion exchanging of the PIL segments. Moreover, the multiple functions (oil/water separation, dye absorption, and antibacterial properties) occurred at the same time, and did not interfere with each other. The multifunctional fibrous filter can be easily regenerated by washing with an acid solution, and the absorption capacity is maintained after many recycling tests. These promising features make PIL-grafted PP nonwoven fabric a potential one-step treatment for multicomponent wastewater.