The material differentiation of engineering plastic sheet and bar can be carried out from multiple dimensions, mainly including chemical composition, use or function, heat resistance and so on. The following are the differences between these materials:
First, according to chemical composition
Crystalline engineering plastics: In the solidification process of this type of plastic, the molecules will be arranged into an ordered crystal structure, such as some PA (polyamide, commonly known as nylon) varieties.
Amorphous engineering plastics: In contrast to the crystalline type, the molecular arrangement of amorphous engineering plastics is relatively disordered, and there is no crystal structure, such as PC (polycarbonate).
Second, according to the use or function of the distinction
General engineering plastics: mainly include polyamide (PA), polycarbonate (PC), polyformaldehyde (POM), thermoplastic polyester (such as PBT and PET) and so on. These plastics have a wide use temperature range and a long use, can withstand the role of mechanical stress, widely used in automobiles, electronic appliances, machinery and other fields.
Special engineering plastics: including fluorine plastics, polyimide (PI), polyphenylene sulfide (PPS), polysulfone (PSU), polyether ether ketone (PEEK), polyaryl ester (PAR), polyphenyl ester (PHB), liquid crystal polymer (LCP), etc. This kind of plastic has higher heat resistance, corrosion resistance, wear resistance and other special properties, suitable for areas with higher material performance requirements, such as aerospace, electronic appliances, medical and so on.
Three, according to heat resistance
General engineering plastics: the use temperature is generally about 100-150 degrees, such as PA, PC, POM and so on.
Special engineering plastics: long-term use temperature above 150 degrees, such as PEEK, PI, etc. These plastics can still maintain excellent performance at high temperatures to meet special needs.
4. Specific material characteristics and applications
Polyamide (PA) : known for its low specific gravity, high tensile strength, wear resistance, good self-lubrication and excellent impact toughness. Widely used in automotive and transportation industry pump impeller, blade, seat, bushing, bearing and other parts.
Polycarbonate (PC) : has similar strength to non-ferrous metals, has both ductility and toughness, and has very high impact strength. It is widely used in lamp shade, signal lamp, transparent protective plate of stadium and stadium, automobile mirror and so on.
Polyformaldehyde (POM) : has similar hardness, strength and stiffness to metal, and has good self-lubricity over a wide range of temperature and humidity. Widely used in electronics, machinery, instruments, daily light industry, automotive and other fields.
Special engineering plastics (such as PEEK, PI) : with higher heat resistance, corrosion resistance, wear resistance and other special properties, suitable for higher material performance requirements in the field, such as aerospace, electronic appliances, medical and so on.
