Natural rubber is an amorphous body with the ability to crystallize. Natural material (untreated) - carbon is colorless or white. Natural rubber does not dissolve in alcohol, water, acetone and some other liquids. In aromatic and fatty hydrocarbons (ethers, benzene, gasoline and others), it swells and subsequently dissolves. As a result, colloidal solutions are formed, which are widely used in technical needs.
Natural rubber has a uniform molecular structure. The material has high physical and technological characteristics, is easily processed on the appropriate equipment.
Natural rubber is highly elastic (resilient). A material is able to restore its original form when the forces that cause its deformation cease to act on it. It should be said that elasticity is maintained in a fairly wide temperature range. However, prolonged storage provokes hardening of the material.
Natural rubber at a temperature of minus one hundred and ninety-five degrees is transparent and hard, at a temperature of zero to ten degrees - opaque and brittle, at twenty - translucent, elastic and soft. When heated above 50 ° C, the material becomes plastic and sticky.
It loses its elasticity at a temperature of more than eighty degrees, at one hundred and twenty degrees, it passes into a resinous liquid state, after hardening it is impossible to obtain the initial product. When the temperature rises to two hundred to two hundred and fifty degrees, natural rubber begins to decompose. The result is a series of liquid and gaseous substances.
Natural rubber is a good dielectric. In addition, the material has low gas and water resistance.
The material is quite slowly oxidized by atmospheric oxygen. Faster process occurs under the influence of chemical oxidizing agents.
Among all other properties, rubber has plasticity. He is able to maintain the form that he acquired under the influence of external influences. Plasticity, which manifests itself during machining and heating, is considered one of the distinguishing characteristics of the material. Due to the fact that rubber has elastic and plastic properties, it is also called plasto-elastic material.
Natural rubber, the formula of which is (C5H8) n, includes molecules containing a large number of double bonds. The material easily reacts chemically with many substances. The increased reactivity is due to the unsaturated chemical nature of the material. The best interaction occurs in those solutions in which rubber is represented by molecules of relatively large colloidal particles.
When stretched or cooled, a transition of the material to a crystalline state from an amorphous state (crystallization) is noted. This process takes place over time, not so instantly. The crystals have a small size, an indefinite geometric shape, and their faces are fuzzy.
