Structural Features of Styrene-Functionalized Cyclodextrin Polymers That Promote the Adsorption of Perfluoroalkyl Acids in Water

• DOI: 10.1021/acsami.4c01969
• Publication Date: 2024-05-20T18:31:56Z
• Authors: Zhi-Wei Lin; Jieyuan Wang; Yaryna Dyakiv; Damian E. Helbling; William R. Dichtel
• Keywords: Comonomer

Cross-linked β-cyclodextrin (β-CD) polymers are promising adsorbents for the removal of per- and polyfluoroalkyl substances (PFAS) from contaminated water sources, including groundwater, drinking water, wastewater. We previously reported porous, styrene-functionalized (StyDex) derived radical polymerization with vinyl comonomers. Because versatility these polymerizations, StyDex polymer compositions tunable, which facilitates efforts to establish structure–adsorption relationships discover improved materials. Here, we evaluate material properties PFAS adsorption 20 derivatives varied comonomer structure loading, regiochemistry styrene placement on CD monomer, size. A containing N,N′-dimethylbutyl ammonium ions exhibited most effective in batch experiments. Furthermore, a β-CD size-selective host–guest interactions perfluoroalkyl acids (PFAAs) neutral contaminants aqueous electrolyte when compared similar either α-CD or γ-CD. Polymers based monomers an average seven groups randomly positioned over 21 available hydroxyl performed similarly those monomer functionalized regiospecifically at each 6′ positions. The former is prepared single step unmodified β-CD, so ability use it without compromising performance demonstrates promise developing economically competitive adsorbents. These results offered important insights into will inform design formulations.