To systematically explore the effects of the synthesis conditions on the porosity of hyper-cross-linked polymers (HCPs), a series of 9-phenylcarbazole (9-PCz) HCPs (-) has been made by changing the molar ratio of cross-linker to monomer, the reaction temperature , the used amount of catalyst and the concentration of reactants. Fourier transform infrared spectroscopy was utilized to characterize the structure of the obtained polymers. The TG analysis of the HCPs showed good thermal stability. More importantly, a comparative study on the porosity revealed that: the molar ratio of cross-linker to monomer was the main influence factor of the BET specific surface area. Increasing the reaction temperature or changing the used amount of catalyst could improve the total pore volume greatly but sacrificed a part of the BET specific surface area. Fortunately changing the concentration of reactants could remedy this situation. Slightly changing the concentration of reactants could simultaneously obtain a high surface area and a high total pore volume. The BET specific surface areas of was up to 769 m g with narrow pore size distribution and the CO adsorption capacity of was up to 52.4 cm g (273 K/1.00 bar).

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6902873PMC
http://dx.doi.org/10.3762/bjoc.15.279DOI Listing

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