What material is used for inflatable sealing rings? Which rubber is better?

What material is used for inflatable sealing rings? Which rubber is better?

Rubber comes in many varieties, each with its own unique characteristics and specific application requirements. Some synthetic rubbers can combine the properties of two or more materials, but this requires extensive experimentation. Today, we won't delve into the details of various materials and their features, as the material used for inflatable seals is relatively uniform.

Today, we will explore the three commonly used materials for manufacturing inflatable seals by Dahong Plastic & Rubber.

Without a doubt, silicone materials should be chosen for high-temperature environments, as silicone is a highly active adsorption material, classified as an amorphous material with the chemical molecular type of mSiO2·nH2O. It is insoluble in water and any solvent, odorless, non-toxic, and chemically stable, not reacting with any substance. Due to different manufacturing methods, various types of silicone form different microporous structures. The chemical composition and physical structure of silicone determine its high adsorption performance, good thermal stability, stable chemical properties, and high mechanical strength.

2. For aging-resistant environments, choose三元乙丙橡胶 (EPDM, Ethylene Propylene Diene Monomer), as it is a copolymer of ethylene, propylene, and a small amount of non-conjugated diene. Its main chain consists of chemically stable saturated hydrocarbons, with unsaturated double bonds in the side chains, offering excellent ozone, heat, and weather resistance. It is widely used in automotive parts, building waterproof materials, cable sheaths, heat-resistant hoses, tapes, and automotive seals.

Nitrile rubber is commonly used in acidic or alkaline corrosion or oil contamination. It is produced by emulsion polymerization of butadiene. Nitrile rubber is primarily produced using low-temperature emulsion polymerization, offering good oil resistance, high wear resistance, good heat resistance, and strong adhesion. However, it has its drawbacks, such as poor low-temperature resistance, poor ozone resistance, poor insulation, and slightly lower elasticity. Nitrile rubber is mainly used to manufacture oil-resistant rubber products, abbreviated as NBR. It is a synthetic rubber made by copolymerizing butadiene, known for its oil resistance (especially paraffin oil) and good aging resistance.

The three types of rubber materials listed above are commonly used in the production of inflatable seals. According to data provided by Hong Rubber and Plastic, silicone is the most widely used material. Otherwise, choose one of the other two materials unless there is a special requirement for oil resistance or aging resistance. Generally, silicone rubber is preferred for its resistance to aging, acid and alkali, and high temperatures. As for synthetic rubber, a detailed analysis will follow.