Poly(benzyl ether)-type additive to engineer glassy polyimide membranes for enhanced gas separations

Abstract

This conceptual study demonstrates the reinforcement of glassy polyimide membranes by incorporating a poly(benzyl ether)-type additive. Traces of the sterically bulky additive alter the overall physical properties of the entire...

Functional Bisphenol-Based Additive for Controlled Gas Transport and Suppressed Plasticization of Polyimide Membranes

“…We investigated the mechanical properties of membrane samples using a universal tensile machine before and after the addition of aMDMP and thermal treatment. Overall, a pristine 6FDD became notably reinforced with the embedment of the additive (1 wt %), similar to previous results with the macro-additive containing xylenyl units . Then, the additive-embedded membrane was further stiffened after being heated at 200 °C for 5 h. In contrast, the sole matrix polymer was less strengthened without the additive.…”

“…Overall, a pristine 6FDD became notably reinforced with the embedment of the additive (1 wt %), similar to previous results with the macroadditive containing xylenyl units. 44 Then, the additiveembedded membrane was further stiffened after being heated at 200 °C for 5 h. In contrast, the sole matrix polymer was less strengthened without the additive. The representative tensile stress−strain curves are displayed in Figure 2a.…”

Covalent and non-covalent approaches to suppress plasticization of polymer membranes for gas separation

“…In addition, a membrane containing 1 wt% PBE improves the diffusivity of small gas molecules such as H 2 and CO 2 due to the bulky molecular structure of PBE, so it exhibits excellent separation performance for H 2 /CH 4 and H 2 /N 2 . 64 Carbon molecular sieve (CMS) membranes have been fabricated by uniformly incorporating double-stranded polysilsesquioxane (LPSQ) into a polyimide matrix. These CMS membranes achieve high gas separation performance and excellent plasticization resistance, and their physical aging can be delayed with a poly(dimethylsiloxane) coating.…”

“…In addition, a membrane containing 1 wt% PBE improves the diffusivity of small gas molecules such as H 2 and CO 2 due to the bulky molecular structure of PBE, so it exhibits excellent separation performance for H 2 /CH 4 and H 2 /N 2 . 64…”

Tailoring 6FDA-based click cross-linked membranes: modular synthesis and tunable gas separation

“…It was assumed that the introduction of the allyl pendants promoted the random chain entanglement of m6FDD, attributable to the enhanced flexibility of the chains due to the absence of inter-chain hydrogen bonds between the carboxylates. 39–41…”