One-step synthesis of N-containing hyper-cross-linked polymers by two crosslinking strategies and their CO2 adsorption and iodine vapor capture

Abstract

Here, a series of N-containing hyper-cross-linked polymers (HCPs) were synthesized from triphenylamine (TPA) or/and carbazole (Cz) monomers by one-step crosslinking reactions including Scholl coupling and solvent knitting Friedel-Crafts. Especially, the two reactions were also performed separately under adding both of TPA and Cz, and prepared HCP3 and HCP6. Notably, HCP1, HCP2, HCP3 prepared by Scholl coupling possessed better porosity with the Brunauer-Emmett-Teller (BET) surface areas (SBET) of 199.9–534.5 m2/g and micropore volume (Vmicro) of 0.088–0.24 cm3/g, while HCP4, HCP5, and HCP6 synthesized by solvent knitting Friedel-Crafts had inferior SBET (10.8–34.8 m2/g) with meso/macroporous structure. In addition, these HCPs displayed high N contents, various morphologies, and different hydrophobicity. Interestingly, HCP1 ~ HCP3 exhibited high CO2 uptake (104.7–116.3 mg/g) and acceptable CO2/N2 selectivity at 273 K and 1.0 bar, and large isosteric heat of adsorption (Qst) (28.0–46.7 kJ/mol), while the HCP4 ~ HCP6 showed the larger I2 vapor uptake (254.2–324.8 wt%) at 351 K and 1.0 bar than HCP1 ~ HCP3 (136.5–185.6 wt%). The results indicated the porosity especially microporosity played an important role on CO2 capture, while the SBET was not always the dominated factors for I2 vapor adsorption due to the predominant chemical interaction by electrons transfer, and the chemical structure of polymer skeletons should make the large contribution. This work will develop multifunctional polymers prepared by the facile synthetic method, and make a promising adsorbents for CO2 and iodine capture.