What is thermoplastics?
Thermoplastics are a class of plastics that are plastic at a certain temperature, solidify after cooling, and can repeat this process. The molecular structure is characterized by a linear polymer compound, which generally does not have active groups, and does not undergo linear intermolecular crosslinking when heated. Waste products can be reprocessed into new products after recycling. The main varieties are polyolefins (vinyls, olefins, styrenes, acrylates, fluorine-containing olefins, etc.), cellulose, polyether polyesters and Aromatic heterocyclic polymers, etc.
Definition
Thermoplastics are the most widely used plastics. They are formulated with thermoplastic resin as the main component and various additives. Under certain temperature conditions, plastics can soften or melt into any shape, and the shape remains unchanged after cooling; this state can be repeated many times and always has plasticity, and this repetition is only a physical change, which is called thermoplastic. plastic.
Including polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyoxymethylene, polycarbonate, polyamide, acrylic plastics, other polyolefins and their copolymers, polysulfone, polyphenylene ether
Structural Classification
Thermoplastics can be divided into general-purpose plastics, engineering plastics, and special plastics according to their performance characteristics, wide range of uses, and versatility of molding technology.
The main characteristics of general-purpose plastics are: wide application, convenient processing, and good comprehensive performance. Such as polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS), acrylonitrile-butadiene-styrene (ABS) are also known as “five general-purpose plastics”.
The characteristics of engineering plastics and special plastics are: certain structures and properties of high polymers are particularly outstanding, or the molding processing technology is relatively difficult, etc., and are often used in professional engineering or special fields and occasions. The main engineering plastics are: nylon (Nylon), polycarbonate (PC), polyurethane (PU), polytetrafluoroethylene (Teflon, PTFE), polyethylene terephthalate (PET), etc., special Plastics such as “synthetic heart valves” and “artificial joints” such as “medical polymers”.