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 that of steel and 1/2 that of aluminum. The density of foam plastic is low, about 0.01~0.5. G/cm3. The strength calculated per unit mass is called the specific strength, and the specific strength of some plastics is close to that of steel. For example, alloy steel has a tensile strength per unit mass of 160 MPa, while glass fiber plastic can reach 170 to 400 MPa.

2. Edge performance. Plastics have electrical properties, such as small dielectric loss and excellent arc resistance. These properties can be compared with ceramics.

3. Excellent chemical stability. Generally, plastics have good corrosion resistance to chemicals such as acids and alkalis. The chemical resistance of polytetrafluoroethylene is better than that of gold, and it can withstand the corrosion of strong corrosive electrolytes.

4. Anti-friction and good resistance performance. Most plastics have excellent anti-friction, resistance and self-lubricating properties. The friction resistance of many engineering plastics makes use of these characteristics of plastics. When certain solid lubricants and fillers are added to the resistant plastics, its friction coefficient can be reduced or its resistance performance can be further improved.

5. Light transmission and protection performance. Most plastics can be used as transparent or translucent products, among which polystyrene and acrylic plastics are as transparent as glass. The chemical name of glass is polymethyl methacrylate, which can be used as aviation glass material. Plastic films such as polyethylene and polypropylene have good light transmission and warmth retention properties, and are used in large quantities as agricultural films. Plastic has a variety of protective properties, so it is often used as protective products, such as plastic films, boxes, barrels, bottles, etc.

6. Excellent shock absorption and noise reduction performance. Some plastics are flexible and full of elasticity. When they are subjected to frequent mechanical shocks and vibrations from the outside world, they will produce viscous internal friction and convert mechanical energy into them. Therefore, they are used as shock-absorbing and sound-absorbing materials in engineering. For example, bearings and teeth made of engineering plastics can reduce noise, and foam plastic is an excellent shock-absorbing and sound-absorbing material.