PET full name is Polyethylene terephthalate, Chemical is a -OCH 2 - CH2OCOC6H4CO-, abbreviationis . It is high polymer, dehydrated by dehydration of ethylene terephthalate Brendylene terephthalic acid. Ethylene glycol ester is esterified from ethylene terephthalic acid and ethylene glycol. Pet is milky white or pale yellow, highly crystallized polymer, and the surface is smooth. There are excellent physical-mechanical properties in a wider temperature range, long-term use temperature can reach 120 ° C, excellent electrical insulation, even at high-temperature high frequency, its electrical performance is still good, but the electrical resistance is poor, resistance Creep, fatigue, friction resistance, and dimensional stability are very good.
advantage
1. Have good mechanical properties, the impact strength is 3 to 5 times of other films, and the ability to resist.
2, oil resistance, fat resistance, dilute acid, dilute, and most solvent.
3, has excellent high, low-temperature performance, can be used for a long time in the temperature range of 120 ° C, the short-term use can be 150 ° C high temperature, can be resistant to low-temperature resistance, high, high, low temperature, and small effects.
As shown in Figure 4, the penetration rate of gas and water vapor is low, that is, it has excellent gas barriers, water, oil, and odor performance.
5, high transparency, can block ultraviolet rays, good gloss.
6, non-toxic, tasteless, health safety, can be used directly in food packaging.
PET is a milky white or light yellow highly crystalline polymer, the surface is smooth, the glossy resistance, anti-fatigue, friction resistance and size stability, small wear, high hardness, has the largest toughness in thermoplastic materials: electrical insulation Good performance, is small due to temperature, but poor resistance is poor. Temperature, weather resistance, anti-chemical drug stability, low water absorption, weak acid, and organic solvent, but not hot water-soaked, no alkali-resistant, the glass transition temperature is high, the crystallization speed is slow, the molding cycle Long, long molding cycle, large formation shrinkage, poor dimensional stability, formation of crystallization, low heat resistance, etc. Through the improvement of crystalline and fiberglass increase,
PET has the following features except for PBT properties:
1. The thermal deformation temperature and long-term use temperature are the highest in thermoplastic general materials.
2. Because of heat resistance, reinforced PET is impregnated in a solder bath at 250 ° C, almost no discoloration, particularly suitable for electron, electrical parts for preparing tin soldering.
3, bending strength at 200 MPa, elastic modulus 4000MPa, creep resistance and fatigue resistance, high surface hardness, mechanical properties are similar to thermoset plastics.
As shown in Figure 4, since the price of ethylene glycol used in the production of PET is almost inexpensively half of the butanediol used in the production, PET resin and enhancement PET are the lowest prices in engineering plastics, with high-cost performance.
