| Abstract
| - A new aromatic periodic mesoporous organosilica material containing benzene functional groupsthat are symmetrically integrated with three silicon atoms in an organosilica mesoporous framework isreported. The material has a high surface area, well-ordered mesoporous structure and thermally stableframework aromatic groups. The functional aromatic moieties were observed to undergo sequential thermaltransformation from a three to two and then to a one point attachment within the framework upon continuousthermolysis under air before eventually being converted to periodic mesoporous silica devoid of aromaticgroups at high temperatures and longer pyrolysis times. The mesoporosity of the material was characterizedby powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), and nitrogen porosimetry,whereas the presence and transformation of the aromatic groups in the walls of the materials werecharacterized by solid-state NMR spectroscopy, mass spectrometry, and thermogravimetric analysis. Theattachment of a benzene ring symmetrically onto three siloxanes of the framework was used advantageouslyas a cross-linker to enhance the thermal stability of the organic group. Some of these properties areinvestigated in comparison with other aromatic PMOs that have only two point attachments and anamorphous phenylsilica gel that has only one point attachment. The successful synthesis of the first aromaticPMO with its organic group attached within the framework through more than two points is an importantstep toward the synthesis of PMOs having organic groups with more complex and multiple attachmentswithin the framework.
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