Solvent Effects in the Hydrolysis of Magnesium Methoxide, and the Production of Nanocrystalline Magnesium Hydroxide. An Aid in Understanding the Formation of Porous Inorganic Materials

The hydrolysis of magnesium methoxide in various solvent−methanol mixtures with a water-to-methoxide ratio of 2 has been studied. Solvents having low dielectric constants such as toluene, benzene, and anisole were found to accelerate the gelation process, while solvents having high dielectric constants such as acetonitrile, N, N -dimethylformamide, and dimethyl sulfoxide did not have a significant effect in the gelation process. A correlation between the gelation time and the dielectric constant of the solvents employed was found, which suggests that the solvation of the alcohol−alkoxide mixture is an important parameter which influences the gelation time and hence the resulting properties of the dry gel. This has important implications in the synthesis of porous oxide materials with high surface area.