Pyrene-cored covalent organic polymers by thiophene-based isomers, their gas adsorption, and photophysical properties

Abstract

Two new pyrene-cored covalent organic polymers (COPs), CK-COP-1 and CK-COP-2, were synthesized via the one-step polymerization of two thiophene-based isomers, 1,3,6,8-tetra(thiophene-2-yl) pyrene (L1) and 1,3,6,8-tetra(thiophene-3-yl) pyrene (L2). The resulting pyrene-cored COPs exhibit rather different surface areas of 54 m2 g−1 and 615 m2g−1 for CK-COP-1 and CK-COP-2, respectively. The CO2 uptake capacities of CK-COP-1 and CK-COP-2 also show different values of 2.85 and 9.73 wt % at 273 K, respectively. Furthermore, CK-COP-2 offers not only a larger CO2 adsorption capacity but also a better CO2/CH4 selectivity at 273 K compared with CK-COP-1. CK-COP-1 and CK-COP-2 also exhibit considerable differences in their photophysical property. The different structure and properties of CK-COPs could be attributed to the isomer effect of their corresponding thiophene-based monomers. © 2017 Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2383–2389.