A Pillar[5]arene Conjugated Polymer for Removal of Low-Molecular-Weight Organic Acids, Amines, and Alcohols from Water

We have fabricated a pillar[5]­arene-based conjugated polymer, pillar[4]­arene[1]­terephthalic acid-derivatized poly-p-phenylene pillar[4]­arene[1]­terephthamide (P[5]-PPTA), which demonstrated exceptional adsorption capability toward low-molecular-weight alkylamines, alcohols, and carboxylic acids in water. In addition, P[5]-PPTA could be thermally reactivated and reused at least five times without obvious decrease of adsorption capability. A mechanistic study indicated that the absorption results from the host–guest interaction between the pillar[5]­arene rings in P[5]-PPTA and the low-molecular-weight short-chain alkyl derivatives.