A Fourier transform infrared spectroscopy‐based method for tracking diffusion in organogels
Organogels possess characteristics that make them promising materials for enhancing our understanding of nanostructure‐diffusion relationships in gels and for use in diffusion‐centered applications including drug delivery and nanoreactor media. Unlike hydrogels, however, there are no well‐recognized techniques for measuring the fundamental diffusion parameter of diffusivity, D , in organogels. The present work establishes a technique for measuring D based upon Fourier‐transform infrared spectroscopy. Physically crosslinked gels composed of poly[styrene‐b ‐(ethylene‐butylene)‐b ‐styrene] and aliphatic mineral oil are used to showcase the new technique's capability. Diffusivity of unimers—oleic acid—and reverse micelles—sodium dioctyl sulfosuccinate (AOT)—within as‐prepared and preswollen gels is quantified and resultant values are commensurate with studies of unimer and micelle diffusion in hydrogels. The case of AOT diffusion is further validated through small‐angle X‐ray scattering analysis, which is in close agreement (<20% difference).
Journal of Polymer Science
Mineart, Kenny; Walker, William; Mogollon-Santiana, Joaquin; and Lee, Byeongdu. "A Fourier transform infrared spectroscopy‐based method for tracking diffusion in organogels." (2020) : 1707-1716.