What is the difference between silica and polymer?
Both are made from the linkage of repetitive units. In the case of polymers, it is the repetition of monomer units (styrene, ethylene, glycol, etc.) and for silica, it is the repetition of SiO4. Therefore, the polymer has an organic backbone whereas the silica gel has an inorganic one.
The polymer is more susceptible to leaching, which happens when the polymer condensation is not completed and parts of it can dissolve in organic solvents. The polymer active sites are inside the matrix, so the rate of action is largely dependent on the rate of diffusion through the polymer. Polymer must be used in solvents that will allow it to swell (DCM, THF, CHCl3). This also means that product can get trapped inside the polymer, greatly affecting the yield.
The silica active sites are on the surface, where they are accessible, giving fast kinetics and high yields. Silica gel is not affected in any way by any organic solvent since the pore structure is rigid, permanent, and consequently is mechanically and thermally stable.
Read also:
- What are the advantages of choosing a silica-based product over a polymer-based one?
- What are pros and cons of choosing silica or polymer in solid-phase extraction (SPE)?
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Solutions For Purification and Chromatography (BROPUR)
Brochure, 48 pages. Product lines: SiliaFlash Bulk Irregular Silica for Chromatography, SiliaSphere Bulk Spherical Silica for Chromatography, SiliaBond Chromatographic Phases, SiliaSep Flash Cartridges and SiliaPlate TLC Plates