What are several ways to classify plastics?

There are many kinds of plastics, about 300 kids, and dozens of commonly used plastics. There are also many ways to classify plastics, and there are two commonly used ones. One is divided into two categories: thermoplastics and thermosets, according to the change of performance after heat; the other is divided into general-purpose plastics, engineering plastics, and special plastics, according to different uses.

Thermoplastics are softened and melted under heat, and then shaped after cooling. This process can be repeated several times, and the material always has plasticity. The advantage of this material is that it has good physical and mechanical properties, a simple molding process, and rapid development in variety and production. The disadvantage is that, except for a few varieties, the heat resistance and rigidity are generally poor. Plastics belonging to this type are polyethylene, polypropylene, polyethylene, polystyrene, polycarbonate, polyamide, etc.

Thermosetting plastics are soluble and fusible before molding, under heat conditions, first softening, and then internal chemical changes, and after molding and curing, again under heat no longer melt, nor soluble in organic solvents, only at high-temperature charring. Therefore, thermosetting plastics can only be molded once, and the molding is complicated. The advantages of these plastics are high heat resistance, good dimensional stability, and low price, but their own mechanical properties are poor and need to be reinforced. Such as reinforced with glass fiber After the reinforced plastic, commonly known as "glass fiber reinforced plastic", its strength is comparable to that of metal. Plastics belonging to this type include phenolic resins, epoxy resins, amino resins, etc.

General-purpose plastics are commonly used plastics, which are produced in large quantities and are widely used at low prices. For example, polyethylene, polypropylene, polyvinyl chloride, polystyrene, phenolic plastics, etc. Engineering plastics generally refer to the high mechanical properties, can be used as a class of plastics instead of metal engineering materials. For example, polyamide, polyformaldehyde, polycarbonate, etc. Special plastics refer to plastics with a particular aspect of special performance, such plastics have high heat resistance, corrosion resistance or other special properties, also known as functional plastics—for example, fluoroplastics, silicone plastics, etc.

Thermoset plastics are known for their flexibility, strength, and durability. The excellent performance of thermoset plastics compression molding process makes them ideal for a variety of applications in many industries. Industries such as automotive, aerospace, construction, medical, military, agricultural, and corrosion control use parts made from thermoset plastics. Contact the experts at MDC to find out if thermoset plastic materials are right for your application.