Dimethoxypillar[5]arene knitted porous polymers for efficient removal of organic micropollutants from water

Abstract

Porous organic polymers containing macrocycles are promising adsorbents to remove organic micropollutants from water. However, it is still a big challenge to achieve the balance between economy and performance in real-world application. This study aimed at tackling this challenge by verifying the feasibility of dimethoxypillar[5]arene (P[5]) as a universal knitting crosslinker. Herein, four typical aromatic building blocks were selected and the corresponding P[5] knitted porous polymers with high cost-effectiveness were successfully obtained by a simple Friedel-Crafts reaction with all the yields in excess of 100%. We have demonstrated the significant roles of P[5] content and surface area on the adsorption kinetics and adsorption capacity, respectively. Specially, P[5] knitted 1,3,5-triphenylbenzene (P[5]-TPB) showed the superior adsorption performance among them. The thermodynamic studies certified the spontaneous and exothermic nature, while the mechanism studies revealed that hose-guest and hydrophobic interactions played fundamental roles in the adsorption process. The studies of flow-through adsorption and adsorption at environmentally relevant concentrations further displayed the superior adsorption performance of P[5]-TPB for practical application. The high cost-effectiveness combined with the excellent adsorption properties of P[5]-TPB achieved the balance between economy and performance, demonstrating great potential as promising adsorbent for real-world application. This work paves a way for the synthesis of cost-effective advanced porous polymers with host-guest property for versatile applications.