Graphene oxide functionalized by poly(ionic liquid)s for carbon dioxide capture

Polymerized and Colloidal Ionic Liquids─Syntheses and Applications

The breadth and importance of polymerized ionic liquids (PILs) are steadily expanding, and this review updates advances and trends in syntheses, properties, and applications over the past five to six years. We begin with an historical overview of the genesis and growth of the PIL field as a subset of materials science. The genesis of ionic liquids (ILs) over nano to meso length-scales exhibiting 0D, 1D, 2D, and 3D topologies defines colloidal ionic liquids, CILs, which compose a subclass of PILs and provide a synthetic bridge between IL monomers (ILMs) and micro to macro-scale PIL materials. The second focus of this review addresses design and syntheses of ILMs and their polymerization reactions to yield PILs and PIL-based materials. A burgeoning diversity of ILMs reflects increasing use of nonimidazolium nuclei and an expanding use of step-growth chemistries in synthesizing PIL materials. Radical chain polymerization remains a primary method of making PILs and reflects an increasing use of controlled polymerization methods. Step-growth chemistries used in creating some CILs utilize extensive cross-linking. This cross-linking is enabled by incorporating reactive functionalities in CILs and PILs, and some of these CILs and PILs may be viewed as exotic cross-linking agents. The third part of this update focuses upon some advances in key properties, including molecular weight, thermal properties, rheology, ion transport, self-healing, and stimuli-responsiveness. Glass transitions, critical solution temperatures, and liquidity are key thermal properties that tie to PIL rheology and viscoelasticity. These properties in turn modulate mechanical properties and ion transport, which are foundational in increasing applications of PILs. Cross-linking in gelation and ionogels and reversible step-growth chemistries are essential for self-healing PILs. Stimuli-responsiveness distinguishes PILs from many other classes of polymers, and it emphasizes the importance of segmentally controlling and tuning solvation in CILs and PILs. The fourth part of this review addresses development of applications, and the diverse scope of such applications supports the increasing importance of PILs in materials science. Adhesion applications are supported by ionogel properties, especially cross-linking and solvation tunable interactions with adjacent phases. Antimicrobial and antifouling applications are consequences of the cationic nature of PILs. Similarly, emulsion and dispersion applications rely on tunable solvation of functional groups and on how such groups interact with continuous phases and substrates. Catalysis is another significant application, and this is an historical tie between ILs and PILs. This component also provides a connection to diverse and porous carbon phases templated by PILs that are catalysts or serve as supports for catalysts. Devices, including sensors and actuators, also rely on solvation tuning and stimuli-responsiveness that include photo and electrochemical stimuli. We conclude our view of applications with 3D printing. The largest components of these applications are energy related and include developments for supercapacitors, batteries, fuel cells, and solar cells. We conclude with our vision of how PIL development will evolve over the next decade.

A Sustainable Strategy for Solid-Phase Extraction of Antiviral Drug from Environmental Waters by Immobilized Hydrogen Bond Acceptor

Deep eutectic solvents are a new generation of green solvents composed of hydrogen bond acceptors and donors. However, when used as extractants in liquid–liquid separation, they are difficult to recycle and easy to lose. In order to solve these problems, herein, immobilized hydrogen bond acceptor adsorbent material was prepared for the separation and enrichment of antiviral drug arbidol from seven kinds of environmental water samples by in situ formation of hydrophobic deep eutectic solvents. The structure, morphology and thermal stability of the adsorbents were characterized, the separation and enrichment conditions for the targeted analyte were optimized, and the adsorption thermodynamics and kinetics were investigated. It was found that the adsorbent material could effectively enrich trace arbidol with the recovery more than 95% at the concentration above 7.5 ng/mL, and the enrichment factor was as high as 634.7. Coexisting substances, such as NaCl, KCl, CaCl₂ and MgCl₂, did not interfere with the adsorption of arbidol, even if their concentration was high, up to 1.0 mol/L, and the relative recovery for real samples was in the range from 92.5% to 100.3%. Furthermore, the immobilized hydrogen bond acceptor could be recycled and reused, and the recovery of arbidol was still above 95% after 12 adsorption–desorption cycles. The mechanism study demonstrates that the synergistic effect of hydrogen bonding and π-π stacking is the primary factor for the high adsorption efficiency.

Preparation and Properties of Polyvinylidene Fluoride Nanocomposited Membranes based on Poly(N-Isopropylacrylamide) Modified Graphene Oxide Nanosheets

The nanomaterial of graphene oxide grafting poly (N-isopropylacrylamide) (GO-g-PNIPAAm) was synthesized and PVDF/GO-g-PNIPAAm blended membranes were fabricated by wet phase inversion. In this work, a hydrophilic nanomaterial GO-g-PNIPAAm with poly(N-isopropylacrylamide) (PNIPAAm) grafted on GO, was synthesized by the atom transfer radical polymerization (ATRP) method. The resulting nanomaterial was confirmed by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectrum, and X-ray photoelectron spectroscopy (XPS) analysis. The synthesized GO-g-PNIPAAm was incorporated with polyvinylidene fluoride (PVDF) via phase inversion, and investigated for its temperature sensitivity, porosity, contact angle, scanning electron microscopy, and permeate properties. The water contact angle measurements confirmed that GO-g-PNIPAAm nanomaterial-endowed PVDF membranes with better hydrophilicity and thermo-responsive properties compared with those of the pristine PVDF membranes. Bovine serum albumin (BSA) adsorption experiments suggested that excellent antifouling properties of membranes were acquired after adding GO-g-PNIPAAm. The modified membranes showed good performance when the doping amount of GO-g-PNIPAAm was 0.2 wt %.