Silicone sealants are common building materials for interior decoration and construction. Their curing process directly affects the performance and application effect of the product. So how does silicone sealant cure and what are factors affecting the curing of silicone sealants? This article will give a detailed introduction.
1. The principle of waterproof silicone caulk curing
It cures into an elastic rubber body by reacting with moisture in the air to form an effective seal.
2. Factors affecting the curing of silicone sealants
(1) Temperature
The curing process of silicone sealants is a chemical process. Temperature has an important influence on the speed of its chemical reaction. Generally speaking, when the ambient temperature is high, the curing speed of the sealant will be fast. The common construction temperature is 4℃~40℃. During construction, you must strictly refer to the construction conditions of the sealant bottle. If the temperature is too high (for example, over 40°C), it may cause the adhesion of the sealant to decrease, or even accelerate aging.
At low temperatures, the fluidity of the sealant deteriorates, which may cause construction difficulties.
(2) Humidity
The curing of flexible silicone sealant depends on the moisture in the air. Water reacts with certain functional groups in silicone, triggering a cross-linking reaction that causes the silicone to cure. The higher the humidity in the atmosphere, the faster the curing, and the lower the humidity, the slower the curing.
(3) Type of substrate
The material, surface roughness, and cleanliness of the substrate will also affect the curing speed of silicone sealant. For example, porous substrates such as wood and stone can absorb more water, thereby accelerating the curing process; while non-porous substrates such as glass and metal may slow down the curing process.
(4) Thickness of sealant
If the sealant is applied too thickly, the surface of the sealant will cure, while the internal curing will be insufficient and the colloid will be soft.
In summary, the curing of silicone sealant is affected by many factors. In the actual construction process, it is necessary to select a suitable sealant according to the construction environment and substrate type. In addition, we should follow the manufacturer’s construction requirements.