Brief introduction to PET resin
PET: polyethylene terephthalate
Chemical formula: -OCH2-CH2OCOC6H4CO-
PET, a high polymer, is produced by dehydration and condensation of ethylene terephthalate. Ethylene terephthalate is derived from the esterification of terephthalic acid and ethylene glycol. PET is a milky or light yellow, highly crystalline polymer with a smooth and shiny surface. It has excellent physical and mechanical properties in a wide temperature range, and the long-term use temperature can be up to 120℃, with excellent electrical insulation. Even at high temperature and high frequency, its electrical properties are still good, but poor corona resistance, creep resistance, fatigue resistance, friction resistance and dimensional stability are all very good.
- Good mechanical properties, 3~5 times impact strengththan that of other films, good folding resistance.
- Resistance to oil, fat, dilute acid, dilute alkali, and most solvents.
- It has excellent high and low temperature performance, and can be used for a long time in the temperature range of 120℃, and can be used for a short time in the high temperature range of 150℃, and can be used in the low temperature range of -70℃. In addition, high and low temperature has little impact on its mechanical properties.
- Excellent gas, water, oil and odor resistance.
- High transparency, can block ultraviolet ray, good luster.
- Non-toxic, tasteless, good health and safety, can be directly used for food packaging.
PET resin has high glass transition temperature, slow crystallization rate, long molding cycle, long forming cycle, large shrinkage, poor dimensional stability, brittle crystallization and low heat resistance. Through the improvement of nucleating agent, crystallizer and glass fiber reinforcement, in addition to the properties of PBT, PET has the following characteristics:
- Thermal deformation temperature and long-term service temperature are the highest among thermoplastic general purpose materials.
- Because of the high heat resistance, the enhanced PET is impregnated in a solder bath at 250℃ for 10s, with almost no color change, which is especially suitable for the preparation of electronic and electrical parts of solder welding.
- The bending strength is 200Mpa, the elastic modulus is 4000Mpa, the creep resistance and fatigue resistance are also very good, the surface hardness is high, the mechanical properties are similar to thermosetting plastics.
- Since the price of ethylene glycol used in PET production is almost half that of butanediol used in production, PET resin and reinforced PET are the cheapest in engineering plastics and have high cost performance.
Film and sheet: all kinds of food, medicine, non-toxic and sterile packaging materials;
High-grade packaging materials for textiles, precision instruments and electrical components;
Base materials for audio tapes, video tapes, cinematographic films, computer floppy disks, metal coatings and photographic films; Electrical insulation materials, capacitor film, flexible printed circuit board and film switches and other electronic and mechanical fields.
Packaging bottle: its application has developed from the initial carbonated beverage to the present beer bottle, edible oil bottle, condiment bottle, medicine bottle, cosmetics bottle, etc.
Electronic appliances: manufacturing connectors, winding tubes, integrated circuit housings, capacitor housings, transformer housings, TV fittings, tuners, switches, timer housings, automatic fuses, motor brackets and relays.
Auto parts: such as switchboard cover, firing coil, all kinds of valves, exhaust parts, distributor cover, measuring instrument cover, small motor cover, etc., can also use PET excellent coating, gloss and rigidity, manufacturing the car’s external parts.
Mechanical equipment: manufacturing gear, CAM, pump housing, pulley, motor frame and clock parts, can also be used as microwave oven baking tray, various ceilings, outdoor billboards and models