What Is High-Temperature Vulcanizing Silicone Rubber?

High-temperature vulcanizing silicone rubber is a type of specialty synthetic rubber that boasts unique characteristics not found in many other conventional rubbers. It possesses excellent high-temperature resistance, maintaining good elasticity and stability in high-temperature environments. This feature has led to its widespread application in numerous industries.

Properties of High-Temperature Vulcanizing Silicone Rubber

High-temperature Performance

A notable characteristic of high-temperature vulcanizing silicone rubber is its thermal stability. While its strength at room temperature is only half that of natural or some synthetic rubbers, it still retains a certain level of flexibility, resilience, and surface hardness in environments above 200℃, with no significant change in mechanical properties.

Low-temperature Performance

The glass transition temperature of high-temperature vulcanizing silicone rubber generally ranges from -70℃ to -50℃, with special formulations capable of reaching -100℃, indicating its excellent low-temperature performance. This is of paramount significance in the aviation and aerospace industries.

Weather Resistance

The Si-O-Si bonds in high-temperature vulcanizing silicone rubber are highly stable against oxygen, ozone, and UV rays. It exhibits excellent weather resistance, even without any additional additives.

Electrical Properties

High-temperature vulcanizing silicone rubber exhibits outstanding insulation properties and also has excellent corona and arc resistance.

Physical and Mechanical Properties

Although the physical and mechanical properties of high-temperature vulcanizing silicone rubber at room temperature are inferior to those of general-purpose rubber, they surpass those of general-purpose rubber at high temperatures of 150℃ and low temperatures of -50℃.

Oil and Chemical Resistance

Conventional high-temperature vulcanizing silicone rubber has moderate oil and solvent resistance.

Gas Permeability

At room temperature, high-temperature vulcanizing silicone rubber has a gas permeability for air, nitrogen, oxygen, carbon dioxide, and other gases that is 30-50 times higher than that of natural rubber.

Physiological Inertness

High-temperature vulcanizing silicone rubber is non-toxic, tasteless, and odorless. It does not adhere to human tissue, has anticoagulant properties, and elicits minimal reactivity with body tissues, making it particularly suitable for medical applications.

Applications of High-Temperature Vulcanizing Silicone Rubber

High-temperature vulcanizing silicone rubber is extensively used in aerospace, aviation, electronics, electrical, machinery, automotive, daily sealing, and health care sectors, playing a crucial role in the national economy and everyday life. It also holds significant importance in national defense and high-tech industries.

While the mechanical strength of high-temperature vulcanizing silicone rubber at room temperature is slightly inferior to other rubbers, its performance in harsh environments is exceptionally remarkable. Due to its high elasticity, resistance to extreme temperatures, aging resistance, and biocompatibility, it is primarily used in the aerospace field as an adhesive and solid-state sealing material. High-temperature vulcanizing silicone rubber adhesive is used for flexible bonding and thermal insulation sealing between the structure and insulating layers of aerospace crafts. Solid high-temperature vulcanizing silicone rubber sealing materials are prevalent throughout the aerospace industry, used for sealing in applications such as missile windows, spacecraft docking, gas systems, and so on. For instance, silicone rubber sealing rings and gaskets play crucial roles in isolating the engine bay from the external environment.