Porous aromatic frameworks of co-cured diethynylbenzene (DEB) and vinyltrimethoxysilane (VTMS) with good thermo-oxidative stability

A series of new porous aromatic frameworks (PAA-VTMS) co-cured by diethynylbenzene (DEB) and vinyltrimethoxysilane (VTMS) have been described. Thermally treated PAA-VTMS were also investigated. When the ratio of DEB to VTMS was 1:1 (PAA-VTMS-4), it showed characteristic pores with uniform diameter, confirmed by scanning electron microscope (SEM) and transmission electron microscopy (TEM) analyses. The surface area of PAA-VTMS-4 was up to 457 m 2 /g and its pore size was 7 nm, related to the hyper-cross-linked structure with plentiful benzene units. The co-cured PAA-VTMS samples whose DEB/VTMS ratios were higher or less than 1:1 showed low surface area. CO 2 uptake of PAA-VTMS-4 was 83 cm 3 /g at 0 °C and 72 cm 3 /g at 25 °C. The temperature of 5% weight loss of PAA-VTMS-4 was 388 °C in nitrogen and 346 °C in air. The surface area of the thermally treated sample (OPAA-VTMS-4) was decreased, but its CO 2 uptake was as high as 115 cm 3 /g at 0 °C and 105 cm 3 /g at 25 °C. The OPAA-VTMS-4 sample almost did not decompose in N 2 , and the temperature of its 5% weight loss was 450 °C in air. It showed that PAA-VTMS with its new porous aromatic framework can be used at high temperature.