In the water-based coating system, water-soluble silicone oils and various organic silicone additives play a crucial role as "performance enhancers". They can effectively address some common defects of water-based coatings and endow the coatings with additional special functions. 
Its main function is primarily reflected in improving the application performance of the coating. As an efficient leveling agent, it can reduce the surface tension of the coating, promote its wetting and spreading on the substrate, thereby eliminating brush marks, orange peel defects, etc., and achieving a smooth and glossy paint film. At the same time, it also has excellent defoaming and anti-foaming capabilities, which can prevent excessive bubbles from being generated during production and application, ensuring the appearance and quality of the paint film. Secondly, it can enhance the surface performance and durability of the coating. Coatings with added silicone oil have a lower surface energy, possess certain hydrophobic and anti-adhesion properties, making stains and liquids less likely to adhere, and even if they do adhere, they are easier to be cleaned. That is to say, it gives the coating the functions of easy cleaning and anti-fouling. In addition, this breathable and hydrophobic membrane structure can form a protective layer on the surface of building materials, reducing water penetration-induced freeze-thaw damage and weathering, while allowing water vapor to pass through, meeting the requirements of building energy-saving and breathable. 
A more advanced application is to be used directly as a film-forming material. By preparing a two-component water-based emulsion with vinyl groups and hydrogen-containing polysiloxanes that can cure at room temperature, pure silicone resin coatings can be produced. These coatings possess excellent chemical stability, weather resistance, as well as outstanding anti-fouling and anti-corrosion properties, representing the development direction of high-end water-based industrial protective coatings. Therefore, whether as an additive or the main film-forming material, water-soluble silicone oil is a key technical component for enhancing the comprehensive performance of water-based coatings and developing environmentally friendly high-performance coatings.