Silicone rubber is a kind of rubber whose main chain is composed of silicon and oxygen atoms alternately. Silicon atoms are usually connected with two organic groups.
Main performance:
(1) High temperature performance. The remarkable characteristic of silicone rubber is high temperature stability. Although the strength of silicone rubber at room temperature is only half that of natural rubber or some synthetic rubber, it can still maintain certain flexibility, resilience and surface hardness at high temperature above 200 C, and its mechanical properties have no obvious change.
(2) The glass transition temperature of low-temperature silicone rubber is – 70-50 C, and the special formulation can reach – 100 C, which indicates that the low-temperature performance of silicone rubber is excellent. This is of great significance to the aviation and aerospace industries.
(3) The Si-O-Si bond in weatherproof silicone rubber is very stable to oxygen, ozone and ultraviolet radiation. It has excellent weatherproof without any additives.
(4) Electrical performance. Silicone rubber has excellent insulation performance, corona resistance and arc resistance are also very good.
(5) Physical and mechanical properties. The physical and mechanical properties of silicone rubber at room temperature are worse than those of general rubber, but it is better than general rubber at high temperatures of 150 C and low temperatures of – 50 C.
(6) Oil resistance and chemical reagent resistance. Ordinary silicone rubber has medium oil and solvent resistance.
(7) Gas permeability. At room temperature, the permeability of silicone rubber to air, nitrogen, oxygen, carbon dioxide and other gases is 30-50 times higher than that of natural rubber.
(8) Physiological inertia. Silicone rubber is non-toxic, tasteless, odorless, non-adherent to human tissues, has anticoagulant effect, and has very little reactivity to body tissues. It is especially suitable for medical materials.