Table 4 Comparison between three MMM fabrication methods containing silica
From: Silica applied as mixed matrix membrane inorganic filler for gas separation: a review
Parameter | Solution blending | In-situ sol gel | In-situ polymerization |
|---|---|---|---|
Type of silica | Solid/powder of silica (fumed silica and mesoporous silica) | Silica sol (microporous silica) | Solid/powder of silica (fumed silica and mesoporous silica) |
Type of treatment/reaction | Mechanical stirring | Chemical reaction (sol formation) – Mechanical stirring | Mechanical stirring – Chemical reaction (polymerization) |
Dispersity of silica | Low dispersity, need additional treatment (ultrasonication) | Good dispersity of particle | High interconnectivity between silica particle and polymer matrix |
Prominent factor | Solvent selection | Compatibility of polymer with silica functional group, sometimes need a coupling agent | Compatibilizing agent e.g., undecenoic acid, tri(isobutyl) aluminium |