Compared with other materials, plastics have the following characteristics

2017-06-14

Plastic is a lighter material with relative density between 0.90 - 2.2. Obviously, can plastics float onto the surface of the water? Especially for foamed plastics, because of the micropores, the texture is lighter and the relative density is only 0.01. This property allows plastics to be used in products that require less weight.
Most plastics have good corrosion resistance to acids, alkalis and other chemicals. Especially, commonly known as king of plastic polytetrafluoroethylene (F4), the chemical stability is even better than gold, put in the "aqua" for more than ten hours do not deteriorate. Because of its excellent chemical stability, F4 is an ideal corrosion resistant material. For example, F4 can be used as a material for conveying corrosive and viscous liquid pipes.
Ordinary plastics are bad conductors of electricity. Their surface resistance and volume resistance are very large. They can be expressed in figures of 109 and 1018 ohms. The breakdown voltage is large and the dielectric loss tangent is very small. Therefore, plastics are widely used in the electronic and mechanical industries. Such as plastic insulated control cables.
Generally speaking, the thermal conductivity of plastic is relatively low, equivalent to the steel 1/75 - 1/225, foam microcellular
It contains gas, which is better for heat insulation, sound insulation and shock resistance. For example, the thermal conductivity of polyvinyl chloride (PVC) is only 1/357 of steel and 1/1250 of aluminum. In the heat insulating ability, single glass window than single glass windows 40%, double glass high 50%. After the plastic form and the hollow glass are combined, the utility model can be used in the house, the office building, the sickroom and the guesthouse. The utility model has the advantages of saving the heating in winter and saving the air conditioning expenses in summer.
Some plastic as hard as stone, steel, such as paper, some soft leather; from the plastic hardness, tensile strength, elongation and impact strength and other mechanical properties, wide distribution, great use of choice. Because of the small proportion and high strength of plastics, they have higher specific strength. Compared with other materials, plastics also have obvious disadvantages, such as easy combustion, poor stiffness, high metal resistance, poor aging resistance, and non thermal resistance.