Poly(ionic liquid)s (PILs) are considered to be very promising materials for a variety of high-performance applications, including electrolytes for batteries and as membranes for flue gas separation. Here, thiol-ene ‘click’ photopolymerization has been utilized to prepare a variety of covalently crosslinked, PIL networks which contain an imidazolium functional group. In an effort to improve ionic conductivity and gas permeability of previously described thiol-ene PIL networks from our research group, mono-functional imidazolium ‘ene’ monomers with variable pendant alkyl chain length were incorporated into the PIL networks, maintaining an overall thiol:ene molar ratio of 1.0:2.0. As the alkyl spacer was increased from methyl (C4) to octyl (C8), a noticeable decrease in Tg was observed along with an increase in ionic conductivity (30 % RH). Upon further increasing the alkyl chain length to C16, the Tg was observed to increase, presumably due to side chain stacking within the network. This effect was coupled to a decrease in the ionic conductivity. Gas permeability (CO2, N2), determined using a time-lag gas separation device, was found to increase as alkyl chain length increased (range of 6-28 Barrers), which correlated with % swelling of the networks.

Influence of pendant alkyl chain on the conductive and gas permeability properties of thiol-ene poly(ionic liquid) networks

256th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.