Basic properties of plastic
1. Lightweight and high specific strength. Plastics are light in weight. The density of general plastics is between 0.9~2.3 g/cm3, which is only 1/8~1/4 of steel and 1/2 of aluminum. The density of various foamed plastics is lower, about Between 0.01~0.5 g/cm3. The strength calculated per unit mass is called the specific strength, and the…