(193ag) Gas Transport in Poly(arylene ether sulfones) with Finely Tuned Microstructure and Morphology
AIChE Annual Meeting
2018
2018 AIChE Annual Meeting
Materials Engineering and Sciences Division
Poster Session: Materials Engineering & Sciences (08A - Polymers)
Monday, October 29, 2018 - 3:30pm to 5:00pm
Incorporation of the triptycene unit provided increased overall fractional free volume, higher chain rigidity as well as ultrafine microporosity, leading to excellent combinations of permeability and selectivity relative to the phenolphthalein-based polysulfone and previously reported polysulfones. For example, the triptycene-based polysulfone displayed an ultrahigh H2/CH4 selectivity of 159 and O2/N2 selectivity of 7.4, along with nearly doubled H2 permeability and ~21% higher O2 permeability compared to commercial Bis-A polysulfone. Variations in chain architecture (i.e., homopolymer vs. random vs. multiblock) have led to an unexpected yet exciting trend in gas separation performance. For example, a random copolymer (TRIP-co-PHPHT PSF) containing 1:1 molar ratio of TRIP and PHPHT showed significantly improved separation performance compared to its homopolymer components although its physical properties (e.g., Tg) lied expectedly in-between TRIP-PSF and PHPHT-PSF homopolymers. Specifically, random copolymerization has improved separation performance of TRIP-PSF homopolymer from just below the 1991 upper bound to above the 2008 upper bound for O2/N2 separation. Gas permeation test on multiblock copolymers are underway to further interrogate the effect of membrane morphology on gas transport properties, which is a largely unexplored structure parameter for glassy polymer membrane materials. In this paper, the synthesis, materials characterization, membrane properties and transport properties of this new series of polysulfones will be discussed, with a focus on elucidating underlying structure-property relationships for these new polysulfones.