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Title: A Fourier transform infrared spectroscopy‐ based method for tracking diffusion in organogels
Abstract 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 measuringDbased 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).  more » « less
Award ID(s):
1904047 1828082
PAR ID:
10456871
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Polymer Science
Volume:
58
Issue:
12
ISSN:
2642-4150
Page Range / eLocation ID:
p. 1707-1716
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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