What is the relationship between rubber and plastic? Why are they everywhere?

Plastic and rubber belong to polymer materials, mainly composed of carbon and hydrogen two kinds of atoms, and some contain a small amount of oxygen, nitrogen, chlorine, silicon, fluorine, sulfur and other atoms, its performance is special, the use is also special. At room temperature, plastic is solid, hard and cannot be stretched out of shape. And rubber hardness is not high, elastic, can be stretched longer, stop stretching and can be restored to original state. This is due to their different molecular structures. Another difference is that plastic can be recycled and reused many times, whereas rubber can't be recycled directly, it can only be processed into recycled rubber before it can be used, so you can see the close relationship between them here. Rubber is more widely used because of its characteristics, first of all

The thermal conductivity of rubber is a poor conductor of heat, and its thermal conductivity is about 2.2~6.28 w/m 2•0K when the thickness is 25 mm. It is an excellent heat insulation material. If the rubber is made into a microporous or sponge state, its heat insulation effect will be further improved, and the thermal conductivity will drop to 0.4~2.0 watts. Any rubber parts in use, may be due to lag loss of heat, so pay attention to heat dissipation.

(2) Thermal expansion because there is a large free volume between the rubber molecular chains, when the temperature rises, the internal rotation of the chain segment becomes easier, which will make its volume become larger. The linear expansion coefficient of rubber is about 20 times that of steel. This must be considered in the vulcanization model design of rubber products, because the linear size of rubber products will be 1.2~3.5% smaller than the model. For the same kind of rubber, the hardness of rubber material and raw rubber content also have a greater impact on the shrinkage of rubber material, shrinkage is inversely proportional to hardness, and is directly proportional to the percentage of rubber. The shrinkage of all kinds of rubber in theory is in the order of fluorine rubber > silicone rubber > butyl rubber > nitrile rubber > neoprene rubber > styrene butadiene rubber > natural rubber, which is why rubber is chosen as the main raw material in the pipeline fittings industry. In today's rubber industry development with each passing day, the world's rubber industry sales have exceeded 250 billion DOLLARS, rubber products have become an important commodity in international trade. In the world market, rubber products have formed tire as the center, with industrial and building supplies as the focus, related to rubber shoes, tape and other daily products as