Low cross-linked polyimide aerogel with imidazole for CO2 adsorption

In this study, low cross-linked mesoporous polyimide aerogels with imidazole were successfully synthesized by co-polymerization method at room temperature from DMBZ, ABIA, PMDA, and TAB. This synthesis method is milder than previous that of porous material synthesis. The experimental results show that polyimide aerogel with imidazole is a mesoporous material. The thermal decomposition temperatures of obtained polyimide aerogels are all above 450 degrees C, which exhibited outstanding thermal stability. The microscopic morphology varies with the ratio of DMBZ/ABIA monomers. The specific surface area of polyimide aerogel tends to increase first and then decrease with the increase of ABIA content. The largest specific surface area is 240.87 m(2)/g. However, polyimide aerogel with high specific surface area had not high CO2 adsorption. In contrast, the PAPI-4 sample with smaller specific surface area had higher CO2 adsorption. The maximum CO2 adsorption capacity is 14.20 cm(3)/g, which is comparable to those of previously reported porous organic polymers. This suggests that polyimide aerogel can be used as an adsorbent material. The high CO2 adsorptions may be attributed to the abundance of nitrogen-rich heteroatoms in the polyimide networks.