Monodisperse silica spheres were prepared by hydrolysis and condensation of tetraethoxysilane (TEOS) in a mixture of water, ammonia and ethanol or acetone at 25℃. The spheres were studied with 13C CP-MAS NMR and their carbon contents were determined. It was found that TEOS was hydrolyzed completely during the sythesis process of monodisperse silica particles and that the carbon inside the silica is in the form of free solvent sheilded in the silica, this is, in accord with the mechanism of aggregation growth.
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机译:(54)标题:具有硅酸盐涂层的固体颗粒(54):FESTKoRPERPARTKEL MIT SILKATBESCHICHTUNG(57)摘要:本发明涉及一种具有二氧化硅涂层的固体颗粒的生产方法,其包括以下步骤:将固体颗粒分散为将其涂覆在水性介质中以产生固体颗粒分散体,通过缓冲系统调节固体颗粒分散体的pH以产生缓冲的固体颗粒分散体,并向缓冲的固体颗粒分散体中添加碱性硅酸盐溶液以形成二氧化硅在涂覆期间将其涂覆在固体颗粒上,其中选择缓冲体系和碱性硅酸盐溶液的量,使得在添加碱性硅酸盐溶液之前和在添加完成之后,缓冲的固体颗粒分散体的pH至少为7.0。碱性硅酸盐溶液的最大含量为11.0。固体颗粒优选是无机固体,特别是