The natural rubber we usually refer to refers to the solid substance obtained from natural rubber latex collected from rubber trees through processing processes such as solidification and drying. Natural rubber is a natural polymer compound mainly composed of polyisoprene, with the molecular formula (C5H8) n. Its rubber hydrocarbon (polyisoprene) content is over 90%, and it also contains small amounts of protein, fatty acids, sugar, and ash.

The physical properties of natural rubber. Natural rubber has high elasticity and slight plasticity at room temperature, with excellent mechanical strength, low hysteresis loss, and low heat generation during multiple deformations. Therefore, its bending and flexibility are also good, and because it is a non-polar rubber, its electrical insulation performance is good. [2]

Rubber, together with plastic and fiber, is known as the three major synthetic materials and is a polymer material with high elasticity and high elasticity. The first characteristic of rubber is that its elastic modulus is very small and its elongation is high. Secondly, it has excellent resistance to breathability, as well as resistance to various chemical media and electrical insulation. Some special synthetic rubbers have better oil and temperature resistance, and can resist the swelling of fatty oil, lubricating oil, hydraulic oil, fuel oil, and solvent oil; Cold resistance can be as low as -60 ℃ to -80 ℃, and heat resistance can be as high as+180 ℃ to+350 ℃. Rubber is also resistant to various types of bending and deformation due to low hysteresis loss. The third characteristic of rubber is its ability to blend, blend, and composite with various materials, thereby modifying them to achieve good comprehensive properties.