Fe3+ mediated self-assembling of polyarylene ether nitrile block copolymer into cationic dye adsorptive sub-micrometer spheres

Polymeric adsorbents normally need to be chemically crosslinked to be effective in aggressive scenarios, which thus triggers the non-recyclable concern of crosslinked plastics. In this study, we firstly synthesized a novel thermoplastic polyarylene ether nitrile (PEN) block copolymer containing pendant carboxyl and sulfonate groups, which were employed to prepare the sub-micrometer PEN spheres with rough surface and porous morphology via a Fe3+ mediated emulsion self-assembling protocol. Furthermore, the obtained PEN microspheres (MS) demonstrated a maximum adsorption capacity of 738 mg/g towards methylene blue (MB), and more than 90% of MB can be removed at 90 °C for 5 min.