How much do you know about the properties and uses of natural rubber?

Natural rubber (NR) is a natural polymer compound with cis-1,4-polyisoprene as the main component. 91% to 94% of its components are rubber hydrocarbons (cis-1,4-polyisoprene), and the rest are non-rubber substances such as proteins, fatty acids, ash, and sugars. Natural rubber is the most widely used general rubber. So how much do you know about the properties and uses of natural rubber? Let’s take a look with the editor.

1. Properties of natural rubber

Elasticity of natural rubber The elasticity of its raw rubber and vulcanized rubber with a low crosslink density is high. For example, in the range of 0-100℃, the elasticity is between 50-85℃, and its elastic modulus is only 1/3000 of that of steel, the elongation can reach 1000%, and the stretching to 350%. Afterwards, the retraction and permanent deformation are only 15%. The elasticity of natural rubber is relatively high, second only to butyl rubber among general rubbers.

The strength of natural rubber Among elastic materials, the strength of natural rubber, mixed rubber and vulcanized rubber are relatively high. The tensile strength of unvulcanized rubber is called Green strength. The Green strength of natural rubber can reach 1.4~2.5Mpa. Appropriate Green strength is necessary for rubber processing and forming. Natural rubber has a high tear strength, up to 98kN/m, and has good wear resistance. The reason for the high mechanical strength of natural rubber is that it is a self-reinforced rubber, which will oriented the macromolecular chains in the stress direction to form crystallization.

Electrical properties of natural rubber Natural rubber is a non-polar substance and is a better insulating material. When the natural rubber is vulcanized, polar factors such as sulfur, accelerators, etc. are introduced, thereby degrading the insulation performance.

Media resistance of natural rubber Natural rubber is a non-polar substance that is dissolved in non-polar solvents and non-polar oils. Natural rubber is not resistant to cyclohexane, gasoline, benzene and other media. Unvulcanized rubber can dissolve in the above media, while vulcanized rubber swells. Natural rubber is insoluble in polar acetone and ethanol, and even more insoluble in water. It is resistant to 10% hydrofluoric acid, 20% hydrochloric acid, 30% sulfuric acid, 50% sodium hydroxide, etc.

2. Main uses of natural rubber

Because of its strong elasticity and good insulation, plasticity, water and air barrier, tensile and wear resistance, natural rubber is widely used in industry, agriculture, national defense, transportation, transportation, machinery manufacturing, medical and health fields and daily life, such as tires used in transportation; transport belts, transmission belts, various sealing rings used in industry; gloves and blood transfusions; rubber shoes, raincoats, water heating bags used in daily life are all made of rubber as the main raw material. Aircraft, cannons, tanks used in national defense, and even rockets, artificial satellites, spacecraft, space shuttles, etc. in the field of science and technology all require a large number of rubber parts.

It was not until 1736 that France first reported the origin of rubber, the method of collecting latex and the local utilization of rubber in South America in the world, which made Europeans begin to understand natural rubber and further study its utilization value. The above is a related introduction to the properties and uses of natural rubber, and I hope it can help you.