Preparation of Modified Silane Composite Emulsion and Its Effect on Surface Properties of Cement-Based Materials

A new type of waterproofing composite emulsion with high silane content and good economic efficiency was synthesized by sol synthesis. The effects of the amount and proportion of the compound emulsifier, amount of tetraethyl orthosilicate, and mixing time on the properties of the emulsifier were investigated. The optimum conditions for the synthesis of a tetraethyl orthosilicate/isobutyl triethoxysilane emulsion were determined. The composite emulsion was characterized by infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and energy-dispersive spectrometry, along with a series of microscopic testing techniques. It was verified that the composite emulsion was coated on the surface of the paste to form a hydrophobic protective layer. The results show that the composite emulsion can achieve a permeability and impervious effect after coating the concrete material, and microhardness tests prove that the composite emulsion will not reduce the surface hardness of cement-based materials.