Gas-separation and physical properties of ABA triblock copolymers synthesized from polyimide and hydrophilic adamantane derivatives. (12th August 2020)

• Record Type: Journal Article
• Authors: Ito, Tsubasa; Shiota, Ryunosuke; Taniguchi, Naomi; Spontak, Richard J.; Nagai, Kazukiyo
• Is Part Of: Polymer. Volume 202(2020)
• Publication Date: 2020-08-12
• Subjects: Polyimide -- Adamantane -- Gas separation -- Block copolymer -- Membrane; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2020.122642
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: In this study, ABA triblock copolymers derived from 4, 4'-(hexafluoroisopropylidene)-diphthalic anhydride-2, 3, 5, 6-tetramethyl-1, 4-phenylenediamine (6FDA-TeMPD; PI) and 3-hydroxy-1-adamantyl methacrylate (HAdMA) or 3, 5-dihydroxy-1-adamantyl methacrylate (DHAdMA) have been synthesized via atom transfer radical polymerization to generate mechanically tough and thermally stable gas-separation membranes with composition-tunable transport properties. Due to the inherent thermodynamic incompatibility between the chemically dissimilar blocks, these two series of triblock copolymers appear microphase-separated. While the gas permeability coefficients of these triblock copolymer membranes are consistently lower than that of PI due to the reduced fractional free volume of HAdMA and DHAdMA, the solubility coefficients of the copolymers are higher than that of PI due presumably to specific interactions between the polar hydroxyl group(s) and penetrant gas molecules. These triblock copolymers synthesized from PI and hydrophilic adamantane derivatives constitute a new class of nanostructured polymeric materials possessing excellent thermomechanical properties in conjunction with designer gas-separation properties. Graphical abstract: Image 1 Highlights: Triblock copolymers are derived from polyimide and hydrophilic adamantane compounds. The copolymers are microphase-separated and possess dispersed or layered structures. Polyimide chains appear linear and adamantane chains are helical from MD simulations. Copolymer membranes exhibit higher H2 /N2 permselectivity than their parent polymers.