The use of ionic liquids (ILs) as media in radical polymerizations has demonstrated the ability of these unique solvents to improve both reaction kinetics and polymer product properties. However, the bulk of these studies have examined the polymerization behavior of common organic monomers (e.g., methyl methacrylate, styrene) dissolved in conventional ILs. There is increasing interest in polymerized ILs (poly(ILs)), which are ionomers produced from the direct polymerization of styrene‐, vinyl‐, and acrylate‐functionalized ILs. Here, the photopolymerization kinetics of IL monomers are investigated for systems in which styrene or vinyl functionalities are pendant from the imidazolium cation. Styrene‐functionalized IL monomers typically polymerized rapidly (full conversion ≤1 min) in both neat compositions or when diluted with a nonpolymerizable IL, [C2mim][Tf2N]. However, monomer conversion in vinyl‐functionalized IL monomers is much more dependent on the nature of the nonpolymerizable group. ATR‐FTIR analysis and molecular simulations of these monomers and monomer mixtures identified the presence of multiple intermolecular interactions (e.g., π–π stacking, IL aggregation) that contribute to the polymerization behaviors of these systems. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.
Ionic liquids (ILs) have been shown to be effective transdermal penetrants of pharmaceutically active ingredients, including small molecules and proteins. The presence of water within ionic liquids has been demonstrated to play a critical role in their structural organization on the molecular level. However, the impact of water on IL transdermal transport efficacy has yet to be investigated. Herein, a water concentration gradient (0%–100% v/v) is tested to evaluate choline trans‐2‐octenoic (CA2OE)‐mediated transport of a hydrophilic model drug dextran (10000 Da) in an ex vivo porcine skin model.Compared to 2:1, 1:1, 1:4, and 1:5 ionic ratio formulations, 50% v/v CA2OE 1:2‐water evidences the greatest success at transporting dextran to the acceptor fluid. Physicochemical characterization (dynamic light scattering (DLS), scanning electron microscopy (SEM), optical density (O.D.), Fourier transform infrared spectroscopy (FTIR), fluorescent microscopy, and rheology) is conducted to test both bulk and nanoscale‐level CA2OE 1:2–water interactions. It is hypothesized that the presence of microemulsions in the CA2OE 1:2 75% v/v formulation accounted for the severely decreased transport compared to the 50%. It is thus critical to comprehensively consider interactions between IL components, co‐solvents, anddrug molecules when formulating ILs for transdermal transport applications.
more » « less- NSF-PAR ID:
- 10443005
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Therapeutics
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2366-3987
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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