Facile preparation of microporous conjugated polycarbazoles via carbazole-based oxidative coupling polymerization is reported. The process to form the polymer network has cost-effective advantages such as using a cheap catalyst, mild reaction conditions, and requiring a single monomer. Because no other functional groups such as halo groups, boric acid, and alkyne are required for coupling polymerization, properties derived from monomers are likely to be fully retained and structures of final polymers are easier to characterize. A series of microporous conjugated polycarbazoles (CPOP-2-7) with permanent porosity are synthesized using versatile carbazolyl-bearing 2D and 3D conjugated core structures with non-planar rigid conformation as building units. The Brunauer-Emmett-Teller specific surface area values for these porous materials vary between 510 and 1430 m(2) g(-1) . The dominant pore sizes of the polymers based on the different building blocks are located between 0.59 and 0.66 nm. Gas (H2 and CO2 ) adsorption isotherms show that CPOP-7 exhibits the best uptake capacity for hydrogen (1.51 wt% at 1.0 bar and 77 K) and carbon dioxide (13.2 wt% at 1.0 bar and 273 K) among the obtained polymers. Furthermore, its high CH4 /N2 and CO2 /N2 adsorption selectivity gives polymer CPOP-7 potential application in gas separation.

We successfully developed a microneedle patch system integrated with H2O2-responsive mesoporous silica nanoparticles for the glucose-monitored transdermal delivery of insulin.

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Monomer building units play a key role in the porosity and adsorption performance of porous conjugated polymers. Three tetracarbazolyl-substituted monomers (Cz-8–10) with similar molecular structures were designed and prepared in order to tune the porosity and pore size distribution of the obtained porous conjugated polycarbazoles (CPOP-8–10) via FeCl3-promoted carbazole-based oxidative coupling polymerization. Polymers CPOP-8 and CPOP-10 exhibit microporous nature similar to most of reported conjugated microporous polymers. Porosity analysis and adsorption performance indicate that CPOP-9 is predominantly mesoporous. The Brunauer–Emmett–Teller specific surface area of CPOP-9 is up to 2440 m2 g–1, which is the highest specific surface area among the reported porous conjugated polycarbazoles by the same method. Mesoporous CPOP-9 shows higher water vapor uptake capacity (804 mg g–1) than microporous polymers CPOP-8 (208 mg g–1) and CPOP-10 (181 mg g–1) at water saturated vapor pressure and 298 K, which might imply that pore size has a key effect on wettability of the porous polymers. With high specific surface area and pore volume, CPOP-9 exhibits high hydrogen uptake of 5.22 wt % (77 K) and carbon dioxide uptake of 70.0 wt % (298 K) at 18.0 bar. Additionally, the uptake capacity of CPOP-9 for toluene is high up to 1355 mg g–1 at the saturated vapor pressure (298 K). The adsorption performance of CPOP-9 can be comparable with that of the known porous organic polymers with ultrahigh specific surface area, such as PAF-1 and PNN-4, under the same conditions.