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

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 (L(1)) and 1,3,6,8‐tetra(thiophene‐3‐yl) pyrene (L(2)). The resulting pyrene‐cored COPs exhibit rather different surface areas of 54 m(2) g(−1) and 615 m(2)g(−1) for CK‐COP‐1 and CK‐COP‐2, respectively. The CO(2) 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 CO(2) adsorption capacity but also a better CO(2)/CH(4) 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