Hypercrosslinked polymers: controlled preparation and effective adsorption of aniline

A series of microporous polymers was produced via the self-condensation of dichloroxylene which is a typical bischloromethyl monomer for a one-step synthetic process. The influences of experimental conditions including type of solvent, reaction time, and addition amount of catalyst on the polymer properties were systematically investigated. The results showed that Brunauer–Emmett–Teller (BET) specific surface areas and pore volumes of the hypercrosslinked polymers (HCPs) increased rapidly as the increase of reaction time at first and then remained nearly constant. In addition, there is a threshold concentration of catalyst for producing HCPs with high BET specific surface areas and big pore volumes. Under optimal reaction conditions, when 1, 2-dichloroethane was used as solvent, reaction time was 21 h and the molar ratio of catalyst to dichloroxylene was one; the microporous polymer with maximum BET specific surface area of up to 1446.32 m²/g was obtained. Furthermore, the adsorption performance of the as-prepared HCPs was studied using aniline as model adsorbate. The adsorption of aniline followed a pseudo-second-order model, and the adsorption isotherm was proved to fit the Langmuir adsorption model (R² > 0.99). The maximum adsorption capacity of aniline could reach 769.23 mg/g at 20 °C.