Preparation of new triptycene- and pentiptycene-based crosslinked polymers and their adsorption behavior towards aqueous dyes and phenolic organic pollutants

Rigid triptycene- and pentiptycene-based monomers, with intrinsic hierarchical structures, were polymerized using tetrafluoroterephthalonitrile as the crosslinker to fabricate crosslinked porous architectures named P1 and P2. The reaction is simple and can be conducted at a relatively mild temperature. Both P1 and P2 exhibit good thermal stability, and good adsorption performance for dyes and phenolic organic pollutants including MB, MO, Pol and BPA. The removal efficiency of P2 is >99% within 10 min for BPA and an adsorption equilibrium for Pol can be reached within 5 min. The adsorption kinetics fit the pseudo-second-order model and the adsorption isotherms follow the Langmuir model and the maximum adsorption capacity of P1 and P2 for BPA can reach 212.06 mg g−1 and 330.02 mg g−1, respectively. In addition, the obtained crosslinked polymers show a highly selective adsorption capacity towards phenolic organic pollutants. Featuring a simple synthesis, porous architecture and efficient adsorption capability, such triptycene-based and pentiptycene-based crosslinked polymers may be ideal adsorbents for water treatment and purification