Synthesis of ethylene glycol-silica

Only one paper that we are aware of explores a combined synthesis and processing route to aluminosilicates. Kemmitt and Milestone use precursors made by reaction of sodium hydroxide, boehmite [Al(0)OH] and silica in ethylene glycol in a 4 3 1 ratio160. The precursor structures are related to those shown above. On removal of solvent (ethylene glycol) a glycolate precursor is obtained that contains a pentacoordinated... 

One of the most significant results in solvothermal chemistry reported thus far is the synthesis of silica-sodafite, reported by Bibby and Dale, which has never been prepared in aqueous systems. Ethylene glycol was used as the solvent in this synthesis, and it was shown that ethylene glycol is fiapped in the cage of the sodalite. ... 

To act as an SDA, a molecule must fulfil certain other prerequisites besides stability [5-7]. A critical factor is its solubility in the solvent used (usually water). The potential SDA must possess at least a limited solubility to take part in the reaction. However, if the solubility is too high or if the SDA forms strong hydrogen bonds with water, then its tendency to co-crystallize with the silica will be low and it will prefer to stay in solution. For this reason, alcohols are only weak SDAs, for instance. The fact that ethylene glycol and ethanolamine are grouped with other SDAs for the synthesis of silica sodalite in Fig. Id seems to contradict this conclusion. However, these molecules act as SDAs only in solvothermal synthesis, in which the SDA simultaneously acts as the solvent. 

T. Chatelain, J. Patarin, M. Soulard, J.L. Guth, and P. Schulz, Synthesis and Characterization of High-Silica EMT and FAU Zeolites Prepared in the Presence of Crown-Ethers with Either Ethylene-Glycol or 1,3,5-Trioxane. Zeolites, 1995, 15, 90-96. 

Mixed solutions of cationic surfactants and nonionic poly(ethylene glycol) or block copolymers were employed for the synthesis of monolithic trimodal porous silica.[176] Lyotropic mixtures of block copolymers of different lengths with hydrophilic linear PEO chains were also applied to their nanocasting into bimodal micro-mesoporous silica to formulate the dependence of the mesopore sizes and the microporosity on the lengths or sizes of the hydrophobic and the hydrophilic blocks, but the mesostructures were worm-type in morphology and several hundred nanometers or more in size. 

Optically active synthetic polymers such as poly(trityl methacrylate) supported on silica gel [7,8] as well as poly(ethylene glycol dimethacrylate) cross-linked in the presence of an optically active template [9] have found general use as chiral stationary phases for the optical resolution of various racemates by chromatography. A current area of investigation concerns the use of optically active polymers as reagents and catalysts for asymmetric synthesis [10,11,12]. 

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