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What is the difference between pet and PE materials

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1. Pet is a milky white or light yellow, highly crystalline polymer with smooth and shiny surface. It has excellent physical and mechanical properties in a wide temperature range. Its long-term service temperature can reach 120 ℃, and its electrical insulation is excellent. Even under high temperature and high frequency, its electrical performance is still good, but it has poor corona resistance, creep resistance, fatigue resistance, friction resistance and dimensional stability

2. PP: polypropylene. Odorless, tasteless and non-toxic. It is the lightest one of the commonly used resins. Excellent mechanical properties. Good heat resistance, continuous service temperature up to ll0-120 ℃. It has good chemical stability and has no effect with most chemicals except strong oxidants. Excellent water resistance. Excellent electrical insulation. However, it is easy to age and has poor impact strength at low temperature. Application field & nbsp; Used for making injection molding products, films, pipes, plates, fibers, coatings, etc. It is widely used in household appliances, automobile, chemical industry, construction, light industry and other fields

3. PE: polyethylene is tasteless and non-toxic. Resistant to chemicals, insoluble in solvents at room temperature. Low temperature resistance, minimum service temperature – 70 ~ – 100 ℃. Good electrical insulation and low water absorption. Physical and mechanical properties vary with density. In industry, low-density polyethylene is mainly polymerized by free radicals at high pressure (110 ~ 200MPa) and high temperature (150 ~ 300 ℃)

others use low-pressure coordination polymerization. Sometimes the same set of equipment can produce polyethylene products with density of 0.87 ~ 0.96g/cm3, which is called full density polyethylene process technology. Polyethylene can be processed into films, wire and cable sheaths, pipes, various hollow products, injection molded products, fibers, etc. It is widely used in agriculture, packaging, electronics and electricity, machinery, automobile, daily sundries and so on

extended data:

glass fiber reinforced pet is suitable for electronic, electrical and automotive industries. It is used for various coil frames, transformers, televisions, recorder parts and housings, automotive lamp holders, lampshades, white heat lamp holders, relays, selenium rectifiers, etc. At present, the consumption proportion of PET engineering plastics in several application fields is: Electrical and electronic 26%, automobile 22%, machinery 19%, appliances 10%, consumer goods 10%, and others 13%. At present, the consumption of pet accounts for only 1.6% of the total

1. 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 of audio tape, video tape, film, computer floppy disk, metal coating and photosensitive film; Electrical insulating materials, capacitor film, flexible printed circuit board, film switch and other electronic and mechanical fields

2. Application of packaging bottle: its application has developed from the initial carbonated beverage to beer bottle, edible oil bottle, condiment bottle, medicine bottle, cosmetics bottle, etc

3. Electronic and electrical appliances: manufacturing connectors, coil winding tubes, integrated circuit housings, capacitor housings, transformer housings, TV accessories, tuners, switches, timer housings, automatic fuses, motor brackets and relays, etc

4. Auto parts: such as distribution panel cover, ignition coil, various valves, exhaust parts, distributor cover, measuring instrument cover, small motor cover, etc. it can also make use of the excellent coating, surface gloss and rigidity of pet to manufacture auto exterior parts

5. Mechanical equipment: manufacturing gears, cams, pump housings, pulleys, motor frames and clock parts. It can also be used as microwave ovens, baking pans, various ceilings, outdoor billboards and models

6. The molding processing of pet plastics can be injection molding, extrusion, blow molding, coating, bonding, machining, electroplating, vacuum metal plating and printing

identification method

1. Smell the taste first. The taste of pet is different from that of ordinary plastics. Burn it with a lighter, and then you will smell a very fragrant and comfortable taste (just burn a bottle to smell). If pet contains other ingredients, the taste is very pungent. One kind of bottle containing SEBS cannot be used

2. If the burned part is too black or the oil drops quickly, most of the melting points are abnormal, which is often found in PET films

3. Wire drawing: when burning, pull the wire on the lighter to see if the wire is long, and then pull the pulled wire to break, and see if the wire is rolled into a small circle at the middle breakpoint. The more it is rolled, the higher the melting point is

there should be no problem with the big bottle, but there should be no problem with it. The key point is to distinguish whether it contains PVC, which is the fatal injury of pet. First, take more samples, and then tile it in a sunny place. PVC is light blue in the sun. If folded in half, there will be white creases. The above is visual identification, with limited accuracy. It mainly depends on experience

there is a more practical and better way. Buy an oven and adjust the temperature to 250 degrees and bake there for half an hour. If the goods contain PVC, there will be many yellow spots on the surface; If the melting point is not enough, it will melt quickly

in fact, there are many kinds of pet to be made, such as pet crushed film, pulp block and roll film with a length of less than 30cm from foreign factories, which have different customer groups

the identification of these goods is strongly required to be tested in an oven. In particular, pet reels are a very scarce supply in the whole market. Generally, the price of films with a length of more than 80 to 120 cm and a thickness of 3-5 filaments is very high (white and transparent)

reference: Baidu Encyclopedia – Pet plastics

boding electronic plastic , customized processing of various insulating materials such as pet, PP and PE

difference between plastic PP, pet and PE

1 Pet

Pet (polyethylene terephthalate) is a plastic material

advantages of PET: plastic has the characteristics of light weight, high transparency, impact resistance and not easy to break. It can also prevent carbon dioxide gas, keep the steam water “gas”, have good preservation, and emphasize the technical trend of heat resistance, pressure resistance and other functions, making pet bottles the main packaging for drinking today. Many drinks that need high-temperature bacteria to be filled, such as flavored water, fruit juice, dairy products, sports drinks and so on, have also been packaged in PET bottles. PET bottles have strictly become the main packaging materials of beverage products. Due to its low environmental pollution and energy consumption, PET bottles are gradually replacing traditional packaging materials with the rise of environmental protection. With its heat-resistant, pressure resistant and other functions, it has nearly replaced all PVC bottles, bags, aluminum cans, iron cans, glass bottles, etc., becoming the packaging material with the most growth potential& nbsp;

2. PP

PP is polypropylene, which has the advantages of transparency, firmness and heat resistance, and the price is lower than that of traditional materials

1. PP bottles can be hot filled at 100 ℃, for example, fruit juice and jam products need to be packaged at this temperature, while the filling temperature of ordinary PET bottles cannot be higher than 76 ℃ of glass transition. BOPP bottles are widely used in the packaging of functional drinks because they can withstand hi
gh temperatures above 100 ℃

2. The water barrier property of PP is about 5 times that of pet. The price of PP preform production equipment is lower than that of pet preform production equipment

3. The processing speed of PP bottle is slower than that of PET bottle, and its physical properties are also poor, which is the main reason why PP bottle can not be widely used

4. PP absorbs and disperses heat more slowly than pet. Therefore, it not only consumes more energy than PET bottles, but also has a longer molding and cooling cycle, resulting in a 25% lower production efficiency of PP than pet

5. The processing temperature of PP bottle blow molding is only 5 ℃. Compared with the processing temperature of PET bottle at 15 ℃, the shutdown rate and scrap rate are greatly increased

6. The oxygen and carbon dioxide permeability of PP bottle is about 30 times that of PET bottle, which makes it impossible to be widely used in the barrier packaging of carbonated drinks like pet& nbsp;

3. PE

PE plastic bottle is a thermoplastic resin prepared by polymerization of ethylene

odorless, non-toxic, feels like wax, has excellent low temperature resistance (the minimum service temperature can reach – 70 ~ – 100 ℃), good chemical stability, can resist the erosion of most acids and bases (not resistant to acids with oxidizing properties), is insoluble in general solvents at room temperature, has small water absorption and excellent electrical insulation performance; However, it is very sensitive to environmental stress and has poor heat aging resistance& nbsp;

the chemical formula of polyethylene terephthalate is – och2 — English Name: pet for short, which is a high polymer and comes from the dehydration condensation reaction of ethylene terephthalate. Ethylene terephthalate is obtained by esterification of terephthalic acid and ethylene glycol. Pet is a milky white or light yellow, highly crystalline polymer with smooth and shiny surface. It has excellent physical and mechanical properties in a wide temperature range. The long-term service temperature can reach 120 ℃, and the electrical insulation is excellent. Even under high temperature and high frequency, its electrical properties are still good, but it has poor corona resistance, creep resistance, fatigue resistance, friction resistance and dimensional stability
advantages
① it has good mechanical properties, the impact strength is 3 ~ 5 times that of other films, and the folding resistance is good.
② resistant to oil, fat, dilute acid and alkali, and most solvents.
③ it has excellent high and low temperature resistance. It can be used for a long time within the temperature range of 120 ℃. It can withstand high temperature of 150 ℃ and low temperature of – 70 ℃ in a short time, and has little impact on its mechanical properties at high and low temperature.
④ low gas and water vapor permeability, with excellent gas, water, oil and odor resistance.
⑤ high transparency, UV blocking and good gloss.
⑥ it is non-toxic, tasteless, hygienic and safe, and can be directly used in food packaging

PP is the abbreviation of PP. its Chinese name is polypropylene, commonly known as 100% discount glue. PP (polypropylene) is prepared by catalytic polymerization of propylene monomer with Ziegler Natta catalyst. It is a crystalline isotactic polymer with regular molecular links. PP (polypropylene) can be divided into isotactic PP (polypropylene) and random PP (polypropylene) according to its crystallinity. Isotactic polypropylene is a highly crystalline thermoplastic resin with a crystallinity of more than 95% and a molecular weight of 80000-150000; Random polypropylene is an amorphous, slightly viscous white wax at room temperature. It has a low molecular weight of 3000-10000, irregular structure, lack of cohesion and less application. The commonly used PP raw material is isotactic polypropylene. Polypropylene is a high polymer. The monomer is propylene CH2 = ch-ch3. Polypropylene is obtained by adding polypropylene
polymerization reaction. The chemical formula can be expressed as (C3H6) n and the structural formula can be expressed as [- ch2-ch (CH3) -] n
application scope
automotive industry (mainly PP containing metal additives: fender, ventilation pipe, fan, etc.), instruments (dishwasher door gasket, dryer ventilation pipe, washing machine frame and cover, refrigerator door gasket, etc.), daily consumer goods (lawn and gardening equipment, such as lawn mower and sprinkler, etc.)
chemical and physical properties
PP is a semi crystalline material. It is harder than PE and has a higher melting point. Because PP products are very brittle when the temperature of homopolymer PP is higher than 0 ℃, many commercial PP materials are irregular copolymers with 1 ~ 4% ethylene or block copolymers with higher ethylene content. Copolymer PP materials have lower heat distortion temperature (100 ℃), low transparency, low gloss and low rigidity, but have stronger impact strength. The strength of PP increases with the increase of ethylene content. Vicat softening temperature of PP

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