A new family of microporous semicrystalline silica materials (MSSMs) were developed at room temperature from acidic mixtures of alkyl-substituted silane and tetramethylalkoxysilane. Hydrolyzed alkyl-substituted silica precursors, having hydrophilic silanol groups and hydrophobic alkyl groups, presumably act not only as templates but also as sol stabilizers for continuous pore engineering of silica materials in the micropore region. Depending on the substituted alkyl (SUA) groups in initial sols, MSSMs have distinct broad x-ray diffraction peaks in low 2θ range of 2° to 12°, distinguishable thermal behavior of SUA groups, highly flexible processability, and discrete micropore size with good thermal stability of micropores after the removal of SUA groups. These designer microporous silicas are expected to be useful for molecular sieving applications.
利用烷基取代
硅烷和四
甲基烷氧基
硅烷的酸性混合物在室温下开发出了一系列新型微孔半结晶
二氧化硅材料(MSSM)。
水解的烷基取代
二氧化硅前体具有亲
水性
硅烷醇基团和疏
水性烷基基团,不仅可以作为模板,还可以作为溶胶稳定剂,用于
二氧化硅材料在微孔区域的连续孔隙工程。根据初始溶胶中取代的烷基(SUA)基团的不同,MSSM 在 2° 至 12° 的低 2θ 范围内具有不同的宽 X 射线衍射峰,SUA 基团的热行为不同,具有高度灵活的可加工性,微孔尺寸离散,去除 SUA 基团后微孔具有良好的热稳定性。这些设计型微孔
硅有望用于
分子筛分应用。