Rubber, plastic, and fiber are named as the three major synthetic materials, and are polymer materials that possess both high stretchability and good elasticity.

The great feature of rubber seals is that it has a very small modulus of elasticity, but a very high elongation. And the rubber seal has quite good air permeability and performance to various chemical media and electrical insulation. Some special synthetic rubbers have very good oil resistance and temperature resistance, and can resist the expansion of fatty oil, lubricating oil, hydraulic oil, fuel oil and solvent oil solution, and its cold resistance can reach - 60°C to -80°C, heat resistance can be as high as +180°C to +350°C.