A New Route to Monolithic Methylsilsesquioxanes: Gelation Behavior of Methyltrimethoxysilane and Morphology of Resulting Methylsilsesquioxanes under One-Step and Two-Step Processing

摘要: Polymerization of methyltrimethoxysliane (MTMS) results in methylsilsesquioxane (MSQ), which has found important applications recent years including use as low-k dielectric materials the semiconductor industry, superhydrophobic materials, monolithic columns, and hybrid matrixes for immobilizing proteins. For polycondensation MTMS ethanolic solutions, we report sol−gel behavior under two different sets conditions. First, examined one-step polymerization over a wide range pH show that initial is determining both gelation MTMS-derived sols morphology resulting MSQ materials. In method, obtained either transparent precipitates and/or macroscopically phase-separated resins when was below isoelectric point (IEP) silanols; or macroporous gels with > IEP; homogeneous solutions close to IEP. We also on of...