Silicone resin has excellent thermal oxidation stability, weather resistance, electrical insulation, hydrophobicity and corrosion resistance. It has been widely used in high and low temperature resistant insulating paint, special coatings, adhesives, film plastics and so on. However, at present, organic compounds such as aromatics and alcohols are mainly used as solvents in silicone resin high and low temperature resistant insulating paint, silicone waterproof coating and special coatings, which will produce a large amount of VOC (volatile organic compounds) and cause great harm to the environment and human body. Therefore, the hydration of silicone resin is the current research hotspot and development trend.

Waterborne silicone resin is a kind of silicone emulsion which is waterborne and dispersed with water as the dispersant of silicone resin. At present, it is widely used in silicone modified coatings, such as silicone modified acrylic emulsion, silicone modified polyurethane emulsion, silicone modified polyester emulsion and so on. The introduction of silicone in the traditional polymer emulsion can enhance its aging resistance, water resistance, high and low temperature, and hardened properties. By introducing silicone chains in the molecular structure of polymer, the commonly used silicone precursors are silane coupling agents, such as silane coupling agent 171560570, etc. These silane coupling agents are three functional alkoxy structures. In aqueous phase, alkoxy groups are hydrolyzed to hydroxyl groups, and hydroxyl groups are further dehydrated and condensed to form cross-linked structures. When the degree of crosslinking is too high, the stability of the emulsion will be affected, resulting in gelation and can not be used. Therefore, the dosage of silane coupling agent is limited, the general dosage is 1~10%, the dosage is too small, the modification effect is not obvious, the dosage is too large, the stability of the emulsion is affected, and the limitation of the dosage determines that the effect of silicon modification is limited or even not obvious.

In addition, the hydrolysis reaction of silane coupling agent occurs in the aqueous phase, and the by-products are low molecular alcohols such as methanol and ethanol, which are flammable and toxic components. For water-based coatings, it is VOC, and VOC is the strictly controlled index of water-based coatings. Therefore, the water-based coatings modified by silane coupling agent can not fundamentally solve the problem of low VOC and zero VOC, which will eventually limit the application.

The industrialization of solventless pure silicone emulsion has solved the above problems. The solventless pure silicone resin is hydrolyzed by silane coupling agent to prepare solid silicone resin. The solid silicone resin does not contain alkoxy, which avoids the release of alcohols in use. Then, a special emulsification process is used to disperse the solid silicone resin in water to form a stable emulsion. Solvent free pure silicone resin not only avoids the introduction of solvent, but also avoids the release of by-product solvent, and fundamentally achieves green environmental protection and zero VOC.

In application, solventless pure silicone emulsion can be mixed with acrylic emulsion, polyurethane emulsion, polyester emulsion, alkyd resin emulsion, fluorocarbon emulsion, wax emulsion and other emulsion in any proportion, without special production process. As long as it is dispersed evenly, it can be used without causing gel, demulsification and unlimited introduction of silicone components, which can maximize the performance of silicone. Both silicon modified coatings and modified silicon coatings can be prepared, giving full consideration to their properties.

Solventless pure silicone emulsion can also be used directly as varnish, and can be used directly in occasions with high transparency requirements, such as wood coatings, which have higher hardness, water resistance and stain resistance than those of existing acrylic emulsion and polyurethane emulsion, and have been successfully applied to concrete, stone, rock wool and other materials without covering the surface appearance, texture or even gloss. Waterproof protection of clay, wood, paper, cultural relics, metal, etc., as well as external wall covering such as water in water (sand) and real stone paint.

Solventless pure silicone emulsions retain the properties of solvent based silicone resins, and can also make special functional coatings, such as silicone heat-resistant coatings, silicone weatherable coatings, silicone insulating coatings, silicone elastomeric coatings, silicone waterproof coatings, etc. Waterborne special functional coatings undoubtedly have a broader development space.

Solventless pure silicone emulsion can be made at room temperature curing, and can also be heated and solidified. It can be used as a two component system or a single component system. It can be used directly and also can be used in combination. It is fundamentally healthy, environmental friendly, green and efficient. It is a great innovation of waterborne coatings. The solventless pure silicone emulsion has boosted the rapid development of waterborne coatings. It can be said without modesty that water paint has ushered in the era of water-based silicone resin!