Plastics are widely used in the packaging industry for their unparalleled performance. More than a quarter of modern plastic production is used to make packaging materials. So what are the plastic packaging materials ? Jiuzhi Plastics Network has summarized the following 11 categories for everyone:
1, polyethylene (PE)
Polyethylene is a high molecular polymer of ethylene and is a thermoplastic. According to its industrial production method, there are high pressure, medium pressure and low pressure polymerization methods. The molecular structure is also very different depending on the production method, and the product performance varies with the molecular structure. Polyethylene is a milky white waxy solid, lighter than water, softer, water resistant, low temperature resistant, odorless, non-toxic, poor heat resistance, poor airtightness of film, sensitive to ultraviolet light. It is easy to oxidize, aging, and has a large change in heat shrinkage and poor printing performance. By its density. Can be divided into high density, medium density, low density polyethylene, and linear low density polyethylene.
2, polypropylene (PP)
Polypropylene is a by-product propylene which is produced by petroleum refining, and is obtained by subjecting a refined propylene monomer to polymerization under the catalyst of a catalyst and then separating from the polymer. The molecular weight is from 100,000 to 500,000, the density is very small, and it is the smallest among the known plastics; it is non-toxic, tasteless, high in transparency, mechanical properties, surface strength, anti-friction, chemical corrosion resistance and moisture resistance; When the above, the impact resistance value is large, but the low temperature impact resistance value is small; it is easy to carry static electricity and the printing performance is poor. Polypropylene has a wide range of raw materials, low prices and wide adaptability to performance. Widely used in the food industry. It is widely used in the manufacture of film and composite film. It has good transparency and surface gloss and can withstand temperatures of 120 degrees. It can be made into a package, blown into a plastic bottle, and some fillers can be added to make certain machine parts.
3. Polystyrene (PS)
Polystyrene is obtained by alkylation of ethylene and benzene under the catalysis of anhydrous tri-alumina to form ethylbenzene, which is then dehydrogenated to obtain styrene. The styrene monomer is heated and polymerized into a polystyrene in an aqueous suspension of an appropriate amount of an initiator (benzoyl peroxide) and a dispersant (polyvinyl alcohol). Polystyrene is a colorless, transparent, non-ductile thermoplastic; non-toxic, odorless, odorless, good coloring, moisture permeability greater than polyethylene, low hygroscopicity, dimensional stability, good gloss; processing properties Good, low cost; mechanical properties increase with increasing molecular weight; low heat resistance, can not be used in boiling water; low temperature resistance, can withstand -40 ° C low temperature; good indoor aging resistance; Mineral oil is well tolerated and has good acid and alkali resistance.
Polystyrene is widely used in the food industry due to its superior performance, low price and wide application. It can be made into films and containers. The shrinkage rate can reach 60-70%. It is a good material for making shrink packaging and has good insulation properties. Can produce a variety of telecommunications parts; can also make a variety of machine parts, toys, daily necessities, etc.; add foaming agent in polystyrene, can make foam, is a good cushioning packaging material.
4, polyvinyl chloride (PVC)
Polyoxyethylene is a vinyl chloride which is subjected to suspension polymerization or emulsion polymerization to form polyvinyl chloride. It has light brown color, transparency and good toughness, and has a density of 1.4g/cm. It has good chemical stability and is not easily corroded by acid and alkali. It has good air tightness, water resistance and heat sealing performance, good printing performance and energy consumption. Less, cheaper; mechanical strength, wear resistance, pressure resistance are better than polyethylene and polypropylene. The main disadvantage is that the thermal stability is poor, it is easily decomposed by heat, and hydrogen chloride gas is released. Due to the variety and quantity of additives, such as plasticizers and stabilizers, PVC can be made into different products, which can produce hard products such as hard pipes and building materials. It can manufacture artificial leather, wire and cable insulation, Plastic flooring, etc. Its main function on the packaging is to make a film, which is divided into soft film, hard film and shrink film. The soft film has a soft texture and good heat sealability, and is suitable for high-frequency sealing; the tensile strength is small, the tear strength is high; the sliding property is poor, and the processing property is also poor. The tensile strength and tear strength of the hard film are large, the texture is hard, the elongation is small; the moisture permeability is small, the gas barrier property is good, the slidability is good; the printing adaptability is good, but the appropriate ink solvent is selected; It has poor temperature resistance and becomes brittle at low temperatures. The shrink film has good transparency, small gas permeability, shrinkage upon heating, wide shrinkage temperature range, and large shrinkage, and is a good heat shrinkable packaging material. According to different production processes, it can be divided into dry stretching. Tubular stretching and longitudinal and transverse uniaxial stretching.
5, polyester (PET)
Polyester is a polycondensation product of terephthalic acid and ethylene glycol. Compared with other plastics, polyester has excellent barrier properties, such as carbon dioxide, oxygen, water and fragrance. It has excellent mechanical properties and high strength, pressure resistance and impact resistance. Good chemical stability, acid and alkali corrosion resistance; high transparency, good gloss and optical properties; non-toxic, odorless, in line with food hygiene standards; ester structure in its structure, so printing performance is good. Polyester is a unique and versatile packaging material. It can be made into a film, made into a packaging container such as a bottle, a can, a cup, etc., and can also be used as a dual-purpose baking tray.
6, phenolic plastic (PF)
The phenolic resin is formed by polycondensation of phenols (mainly phenol) and aldehydes (mainly formaldehyde). Depending on whether the catalyst is acidic or basic, the ratio of phenol to formaldehyde is different. A thermoplastic resin or a thermosetting resin can be obtained. Both can be converted to each other under suitable conditions. In practice, thermosetting resins are often used. Phenolic resin has good mechanical strength and good thermal strength; moisture resistance and corrosion resistance are good; easy to process and low in price.
After the phenolic resin is processed by adding different fillers, curing agents, etc., different phenolic plastics can be obtained. Various flaky fillers are added to the thermosetting resin, and laminated to obtain a variety of properties of the laminate; phenolic foam can be obtained by adding a foaming agent; when the phenolic plastic is used for packaging, the phenolic resin is mixed with the filler and cured. Agents, colorants, etc. are made into molding powders, which are then molded into caps, machine parts, daily necessities, and some packaging containers. Phenolic plastic products have good chemical stability; excellent heat resistance; high mechanical strength, wear resistance; not easy to deform, but poor elasticity; good electrical insulation; monotonous color, mostly dark red or black. Because its main raw materials are phenol and formaldehyde, it has certain toxicity, so it is not suitable for food packaging materials.
7. Polyamide (PA)
Polyamide, commonly known as "nylon", can be obtained by polycondensation of a dibasic acid and a binary. Polyamide is non-toxic, colorless and transparent; good wear resistance. Strong impact toughness, excellent mechanical properties; good light resistance, light aging, good oil resistance, good chemical stability, but not resistant to alcohols, formic acid and phenol; good air tightness; adaptability to temperature, can be -40 Use within ~100 degrees; good printability and decoration; high hygroscopicity.
Polyamides are used in a wide range of applications, such as bearings, gears, pump blades, and automotive parts. Its application on packaging is mainly flexible packaging, which is made into a film for food packaging and can also be used to make straps and ropes, which is more robust than polypropylene strapping.
8, urea-formaldehyde plastic (UF)
Urea-formaldehyde plastics, commonly known as "electric jade", is made from urea and formaldehyde as raw materials, and is obtained by polycondensation reaction to obtain urea-formaldehyde resin, and then added into fillers, colorants, lubricants, plasticizers, etc. into processed plastic powder (electric jade powder), and then The product is heated and molded. It has large surface hardness, certain mechanical strength, and is not easy to deform, but has high brittleness; odorless, odorless, strong coloring power, bright color, similar to jade; good heat resistance, not easy to burn; acid, alkali and water resistance Poor, water absorption is good, and electrical insulation is good. Urea-formaldehyde plastics can be used to make a variety of articles, such as daily necessities, electrical components, and the like. It can be made into a beautiful packaging box, packaging tray, bottle cap, etc. on the bag; because formaldehyde has certain toxicity, it should not be used for food packaging. A urea foam is obtained by adding a foaming agent to a urea resin and mechanically foaming it. It is light weight, low in price, good in heat preservation and corrosion resistant. It is a widely used cushioning packaging material.
9, melamine plastic (ME)
The melamine plastic is the same as the urea-formaldehyde plastic. It is a thermosetting plastic which is obtained by polycondensation reaction of melamine and formaldehyde to obtain a resin as a main component, and is added with a filler, a lubricant, a coloring agent, a hardener, and the like. The melamine plastic is non-toxic, odorless, tasteless and has good hygienic properties; it has high mechanical strength, good surface hardness and is not easy to be deformed; the surface is smooth and feels like porcelain; it has strong impact resistance and pollution resistance; and good chemical stability. Melamine plastics can be used to make packaging containers in a variety of colors including food packaging.
10, polyvinyl alcohol (PVA)
Polyvinyl alcohol is a hydrolysis product of polyvinyl acetate. It is transparent, non-toxic, tasteless; has excellent gas barrier properties, water resistance and oil resistance; good chemical stability; good printability, no static electricity; good mechanical properties. Polyvinyl alcohol uses its film on packaging and can be used for food packaging. It can prevent food from oxidative discoloration, odor and deterioration, and maintain the freshness of food. It can also package other products, such as chemical products.
11, polycarbonate (Pc)
Polycarbonate is a general term for a resin having a carbonate structure in a molecular chain, and generally refers to a bisphenol A type polycarbonate. It is colorless and transparent, has good gloss; excellent heat resistance and cold resistance, and can be used for pressure sterilization; high mechanical strength. It can be juxtaposed with polyester and nylon; it has excellent impact toughness, and the product is not easily broken by impact; it has low water absorption, hygroscopicity and gas permeability; it has good chemical corrosion resistance and can prevent ultraviolet rays from being transmitted through non-toxic, odorless and tasteless; Good molding performance, can be used in general molding methods. The molded product is highly accurate. However, the heat sealing performance is poor.

Short Radius Elbow refers to  that  the radius of curvature is 1 times of the elbow pipe diameter,also referred to as 1D.

Elbow push hot forming process is the use of special elbow pushing machine, mandrel and the heating device, so that pushing pipe raw material to  forward movement in the mold set, be heated in motion, expanding and bending forming process. Elbow push hot deformation characteristics of tube diameter is determined according to the law of constant volume before and after deformation of the metal material, use smaller diameter than the diameter of the elbow, through mandrel to control the deformation process of the blank, to other parts of the compensation due to thinning of the diameter expands, thereby obtaining a uniform wall thickness of the elbow.

Product Name:Short Radius Elbow
Materials: A234 WBP-WP1-WP12-WP11, A403 WP 304-304L-316-316L, A402 WPL3-WPL 6,A860 WPHY 42-46-52-60-65-70,PG370,C20
Thickness: 2mm-100mm 
Crafts: Butt, Push System, Simmer 
Connection: Welding 
Package: Wooden boxes,Wooden pallets,According to customer requirements.
Brand Name: HY 
Place of Origin: China (Mainland) 
Certification: ISO.UKS.SGS.BV 
Application: Chemical, Water, Oil and gas, Electricity
Short Radius Elbow

Short Radius Elbow

Short Radius Elbow,Short Radius,Stainless Steel Short Radius Elbow,Pipe Elbow Radius