Organic silicon, also known as organic silicon compounds, refers to compounds that contain Si-C bonds and have at least one substituent directly connected to silicon atoms. Organic silicon compounds include upstream and downstream products, with upstream mainly being raw materials and downstream mainly being terminal products. The downstream products of organic silicon mainly include four categories: silane, silicone resin, silicone rubber, and silicone oil; Silicone rubber has the highest proportion and is the most widely used and researched category.

Before vulcanization, silicone rubber is a linear polysiloxane with high molar mass, and after vulcanization, it is an elastic body with a network structure; Its unique chemical structure makes it excellent in high and low temperature resistance, weather resistance, ozone resistance, arc resistance, electrical insulation, and other properties.

This classification is based on the vulcanization temperature of silicone rubber, namely high-temperature (heating) vulcanization and room temperature vulcanization.

Specific classification of silicone rubber:
High temperature vulcanized silicone rubber (HTV)
High temperature vulcanized silicone rubber (HTV) is composed of linear polysiloxane (raw rubber) as the skeleton material, added with appropriate reinforcing agents, structural control agents, colorants, vulcanizing agents, etc., and mixed through specific processes. After high-temperature vulcanization, it becomes a network of elastic silicone products. High temperature vulcanized rubber is also known as "solid silicone rubber" due to its high molecular weight polymer long chain, which can endow it with high viscosity.

Due to its excellent physical and mechanical properties, high and low temperature resistance, insulation, breathability, and physiological inertness, high-temperature vulcanized silicone rubber has been processed into various sealing rings, gaskets, cables, pipelines, etc. in industries such as aviation, power, communication, medical, and food, and has been widely used.

Liquid silicone rubber (LSR)
Liquid silicone rubber (LSR) is also an organic silicone rubber that requires high-temperature vulcanization. Compared to high-temperature vulcanized rubber (HTV), which is already in a thick state after mixing and before high-temperature vulcanization, LSR is in a liquid state before vulcanization, hence it is called liquid rubber. Its essence is also to use it as a silicone product after high-temperature vulcanization.

Liquid silicone rubber is widely used in industries such as automobiles, mechanical and process engineering, electrical engineering, food, infant care, and health care.

Room temperature vulcanized silicone rubber (RTV)
Single component room temperature vulcanized silicone rubber (RTV-1)
RTV-1 silicone rubber is a ready-to-use system, which is a mixture of polysiloxane, coupling agent, powder, crosslinking agent, catalyst, etc. mixed in a tube. When used, the rubber material begins to crosslink with water vapor in the air at room temperature, forming an elastomer. Including condensation type single component (releasing small molecules) and addition type single component (silicon hydrogen addition, without small molecule release), addition type can accelerate curing by heating; The most common type is condensation type, such as electronic adhesive, glass adhesive, etc.

Single component room temperature vulcanized silicone rubber is an ideal choice for sealing, bonding, fixing and other applications, and has wide applications in industries such as electronics, lighting, automotive electronics, and construction.

Two component room temperature vulcanized silicone rubber (RTV-2)
RTV-2 silicone rubber, which is composed of components such as polysiloxane, powder, coupling agent, catalyst, etc., divided into two parts A and B. When using, it should be thoroughly mixed in proportion before use; The common ratios are 10:1 (usually condensation type, releasing trace amounts of ethanol small molecules) and 1:1 (usually addition type, without small molecule release, which can be heated to promote its curing rate).

Compared to RTV-1, RTV-2 is more cumbersome to operate, but its deep curing rate is faster, so it is particularly suitable for places with larger thickness of encapsulation or where rapid curing is required for bonding, such as the encapsulation of display screens, inverters, and the sealing and bonding of car lights.