Studies of the pumping effect on the nanoporous microstructure of disordered mesoporous silica materials prepared by calcinations of PMMA-silica hybrids

Abstract We present the first comparative studies of pumping effect (i.e., exhaustive vacuum evacuation) on the as-prepared nanoporous microstructure silica to elucidate the effect of different preparative procedure on a series of obtained disordered mesoporous silica materials. The as-prepared hybrid materials (PMMA-silica) through the pumping treatment exhibited higher thermal decomposition temperature ( T d ) and density ( D ) than these system without pumping treatment based on the studies of thermogravimetric analysis and density measurements and compared with the nanoporous materials by calcinations of PMMA-silica materials was found to exhibit a significant higher value of surface area ( A BET ) based on N 2 adsorption–desorption isotherm. Furthermore, a marked decrease in A BET and V BJH of as-prepared mesoporous silica are observed as the feeding content of TEOS is increased. The morphological images of as-prepared hybrid sol–gel glasses and their corresponding disordered mesoporous silica materials were also studied by scanning electron microscopy and transmission electron microscopy.