Synthesis of Ultramicroporous Materials via Cross-Linking Reaction of Polynaphthalene

Hypercross-linked porous polymer materials have good stability and can be used as needed by adjusting the hydrophobic/hydrophilic degree of its functional groups/ions and surface, and they can achieve high gas adsorption. In this study, a series of hypercross-linked porous polymer materials with a rich pore structure and excellent gas adsorption ability were synthesized from polynaphthalene and dimethoxymethane by adjusting the added amount of the catalyst and cross-linker. The sample prepared under the optimized conditions of adding 18 mmol catalyst and 9 mmol cross-linker gained the specific surface area of 786 m2 g–1 and 0.58 nm ultramicropores taking up 80% of total pores. In addition, its CO2 uptake was up to 2.75 mmol g–1 at 273.15 K/1.0 bar. After carbonization at 800 °C, this sample had a 710 m2 g–1 specific surface area and a monodisperse pore structure with a pore diameter of about 0.4 nm, and its CO2 uptake increased to 3.81 mmol g–1 at 273.15 K/1.0 bar. The adsorption selectivity coefficients of CO2/N2 and CO2/CH4 for the carbonized sample were 8.5 and 2.3, respectively, by using Henry’s law initial slope method.