There are many kinds of silicone sealants. Different kinds of silicone sealants have great differences in temperature resistance, waterproof performance, insulation performance, optical performance, adhesion performance of different materials and softness and hardness. Silicone sealant can be added with some functional fillers to give it the properties of conductivity, thermal conductivity and magnetic conductivity. The mechanical strength of silicone sealant is generally poor, which is also used to make it "breakable" and easy to maintain, that is, if a component fails, only need to pry open the sealant and replace it with a new original, it can continue to use.

The colour of silicone sealant can be adjusted arbitrarily according to the need. Or transparent or opaque or colored. Silicone sealant has excellent performance in shock resistance, electrical performance, waterproof performance, high and low temperature resistance, anti-aging performance and so on.

Two groups of organosilicon sealants are the most common, which include condensation type and additive type. Generally, the adhesive force of condensation type to components and encapsulation chamber is poor, and volatile low molecular substances will be produced during curing process, which has obvious shrinkage rate after curing. The addition (or silica gel) has a very low shrinkage rate and no low molecular weight in the curing process. It can be quickly cured by heating.

LED encapsulation adhesive is a kind of accessories for LED packaging. It has high refractive index and high transmittance. It can protect the LED chip and increase the luminous flux of the LED. It has low viscosity and is easy to defoam. It is suitable for encapsulation and moulding, so that the LED has better durability and reliability.