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PE can be used over a wide manufacturing different processing methods. Ethylene as the main raw material, propylene, 1-butene, hexene copolymer, under the action of the catalyst, as slurry polymerization or gas phase polymerization process, the polymer obtained by flash separation, drying, granulation, etc. a step to obtain uniform particles of the finished product. Including such as sheet extrusion, film extrusion, pipe or profile extrusion, blow molding, injection molding and rotational molding.
▲ extrusion: for the production of extrusion grade typically has a melt index less than 1 and in width to the width of the MWD. In the process, the availability of suitable MI low melt strength. Broader MWD is more suitable for extrusion grades, because they have a higher production speed, lower the die pressure and melt fracture reduction trend.
PE has many extrusion applications, such as wires, cables, hoses, tubes and profiles. Pipes for natural gas applications ranging from a small section of yellow tube to 48in diameter thick-walled clarinet for industrial and municipal pipes. Alternative to large diameter hollow wall made of concrete pipe used for stormwater drains and other sewer pipelines rapidly.
Sheet and thermoforming: Many large picnic-type freezer thermoforming lining is made from PE, with toughness, light weight and durability. Other sheet and thermoformed products include fenders, tank linings, disc bowl guard, transport boxes and cans. One kind of a large number of rapidly growing applications sheet mulch or bottom in the village, which is based MDPE has the toughness, chemical resistance and impermeability.
▲ blow: in the United States sold HDPE1 / 3 or more for blow molding applications. These range from loading bleach, oil, detergent, milk and distilled water bottles to large refrigerator, car fuel tank and the canister. Blow molding grade performance index, such as melt strength, ES-CR and toughness, and the sheets used for thermoforming similar to the application level, it can be used similar to grade.
Injection - blow commonly used in the manufacture of smaller vessels (less than 16oz), used for packaging drugs, shampoo and cosmetics. An advantage of this process is to produce automatically go to the corners of the bottle, as a general blow molding without the later finishing steps like. Although there are some narrow MWD grades for improving the surface finish, the general use of the wide to wide MWD grade.
▲ Injection: HDPE has numerous applications, ranging from thin-walled reusable cup to 5-gsl beverage cans, spending one fifth of domestic production of HDPE. Injection molding grade general melt index of 5 to 10, having a lower mobility grade toughness and have higher liquidity workability grade. Uses include daily necessities and food thin wall packaging; toughness and durability of food and paint cans; highly resistant to environmental stress cracking applications, such as small engine fuel tank and 90-gal trash cans.
Rotational ▲: working method using such a material is generally crushed to a powder material to melt and flow during the thermal cycle. Rotational uses two types of PE: general and cross-linkable categories. General Purpose MDPE / HDPE usual densities ranging from 0.935 to 0.945g / CC, with narrow MWD, the product has a high impact resistance and minimal warpage, its melt index range is generally 3-8. Higher grades usually NA MI, rotomolding products because they do not have the desired impact resistance and resistance to environmental stress cracking resistance.
High Performance Rotational Department of Applied Chemistry can use its unique properties of crosslinked grade. These grades in the first paragraph of the molding cycle, good liquidity, and then cross-linked to form its excellent resistance to environmental stress cracking resistance and toughness. Abrasion resistance and weather resistance. Crosslinked PE can only apply to large containers, ranging from 500-gal tank transport various chemicals to 20,000-gal tank farm.
▲ film: PE film processing is generally flat with ordinary processing or extrusion blown film processing method. Most PE used for films, general density PE (LDPE) or linear low density PE (LLDPE) are available. HDPE film grade is generally used to require superior tensile properties and excellent barrier properties of the place. For example, HDPE film is commonly used in commodity bags, grocery bags and food packaging.
Plastic bucket hazards
A plastic PVC is often used, which is made of polyvinyl chloride resin, a plasticizer and an antioxidant composition of a resin itself has no toxicity. But the added plasticizers, antioxidants and other major toxic materials, household PVC plasticizer, mainly used for dibutyl phthalate, dioctyl phthalate, these chemicals are toxic, PVC antioxidant stearic acid lead salt is toxic. Leaded salt antioxidant PVC (pvc) products and ethanol, ether and other solvents will precipitate lead exposure. PVC containing lead salts used for food packaging and fritters, fried cake, fried fish, cooked meat products, snack foods cake meet, it will make the lead molecules diffuse into the grease to go, so you can not use PVC plastic costumes, food, especially not dressed like oily food.
In addition, PVC products at higher temperatures, around 50 degrees as it will slowly break down the hydrogen chloride gas that harmful, and therefore should not be used as food PVC products packaging. Bakelite (Bakelite) containing free phenol and formaldehyde, have a certain toxicity to humans, is not suitable for the storage of food and food packaging. When electric jade (urea-formaldehyde plastic) although odorless and tasteless, but in 100 degrees boiling water or vinegar is used as food in full bloom, there will be free formaldehyde precipitation, harmful, so it is not suitable as utensils or food packaging. Waste plastics (some might add a little new material) update products, because of its complex composition, it is difficult to ensure without toxicity, it is generally not available to be used as food containing tools and packaging.
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We accept T/T adn L/C