Ebonite rod, Dnipropetrovsk region.

Ebonite is a product of a high degree of vulcanization of natural or gray synthetic rubber. Bound sulfur in ebonite is about 32%, which corresponds to the formula (C6H9S)2. Ebonite is usually dark brown or black in color.
Ebonite is used for the manufacture of parts of electrical appliances, battery tanks and containers for aggressive liquids, as well as for rubberizing chemical equipment.
Ebonite lends itself well to mechanical processing, is not hygroscopic, gas-impermeable, resistant to the action of solutions of acids, bases, salts, vegetable and animal fats; is destroyed by strong oxidizers, aromatic and chlorinated hydrocarbons.(//tractor-service.com)
Ebonite is resistant to aliphatic hydrocarbons, vegetable and animal fats, basic solutions, salts, non-oxidizing acids, and is destroyed in oxidizing agents, aromatic and chlorinated hydrocarbons. A significant disadvantage of ebonite is fragility, especially at low temperatures.

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