Polyethylene

Introduction Polyethene is a instance of polymer that is thermo ductile, meaning that it can be melted to a liquid and remolded as it returns to a solid state. It is chemically synthesized from ethylene, a compound thats usually make from petroleum or innate gas. Other non- send official names for this compound take on polythene or polyethylyne and it is alike abbreviated as PE. It is utilise in making other plastic compounds much often than its used in its pure form. Though it has a wide variety of uses, it can be harmful to humans and to the environment.Members of the polythene group are heavily used in consumer products, and over 60 million tons of these materials are produced planetary every year. For instance, full(prenominal) niggardness polythene (HDPE) is used for products such as milk jugs, detergent bottles, marge tubs, garbage containers, and water pipes. Ultra high molecular weight polyethylene (UHMWPE) is used in can- and bottle-handling machine parts, bearings , gears, joints, and butchers chopping boards, and whitethorn even be make up in bulletproof vests. Low dumbness polyethylene (LDPE) is used for the payoff of rigid containers and plastic film.PolyethyleneDescription Physical propertiesPolyethylene is a thermoplastic polymer consisting of long hydrocarbon chains. Depending on the crystallinity and molecular weight, a thawing pointand nut transition may or may not be observable. The temperature at which these occur varies salubriously with the suit of polyethylene. For common commercial grades of medium- and high-density polyethylene the melting point is typically in the range 120 to 130 C (248 to 266 F). The melting point for average, commercial, low-density(predicate) polyethylene is typically 105 to one hundred fifteen C (221 to 239 F).Chemical propertiesMost LDPE, MDPE and HDPE grades have polished chemical resistance, meaning that it is not attacked by strong acids or strong bases. It is also resistant to gentle oxidant s and simplification agents. Polyethylene burns tardilywith a blue flame having a yellow tip and gives off an odour of paraffin. The material continues burning on removal of the flame outset and produces a drip. Crystalline samples do not dissolve at inhabit temperature. Polyethylene (other than cross-linked polyethylene) usually can be dissolved at grand temperatures in aromatic hydrocarbons such as toluene orxylene, or in chlorinated solvents such as trichloroethane or trichlorobenzene.PolyethylenePolyethyleneIntroduction Polyethylene is a type of polymer that is thermoplastic, meaning that it can be melted to a liquid and remolded as it returns to a solid state. It is chemically synthesized from ethylene, a compound thats usually made from petroleum or natural gas. Other non-official names for this compound include polythene or polyethylyne and it is also abbreviated as PE. It is used in making other plastic compounds much often than its used in its pure form. Though it has a wide variety of uses, it can be harmful to humans and to the environment.Members of the polyethylene group are heavily used in consumer products, and over 60 million tons of these materials are produced worldwide every year. For instance, high density polyethylene (HDPE) is used for products such as milk jugs, detergent bottles, margarine tubs, garbage containers, and water pipes. Ultra high molecular weight polyethylene (UHMWPE) is used in can- and bottle-handling machine parts, bearings, gears, joints, and butchers chopping boards, and may even be found in bulletproof vests. Low density polyethylene (LDPE) is used for the production of rigid containers and plastic film.PolyethyleneDescription Physical propertiesPolyethylene is a thermoplastic polymer consisting of long hydrocarbon chains. Depending on the crystallinity and molecular weight, a melting pointand glass transition may or may not be observable. The temperature at which these occur varies strongly with the type of pol yethylene. For common commercial grades of medium- and high-density polyethylene the melting point is typically in the range 120 to 130 C (248 to 266 F). The melting point for average, commercial, low-density polyethylene is typically 105 to 115 C (221 to 239 F).Chemical propertiesMost LDPE, MDPE and HDPE grades have excellent chemical resistance, meaning that it is not attacked by strong acids or strong bases. It is also resistant to gentle oxidants and reducing agents. Polyethylene burns slowlywith a blue flame having a yellow tip and gives off an odour of paraffin. The material continues burning on removal of the flame source and produces a drip. Crystalline samples do not dissolve at room temperature. Polyethylene (other than cross-linked polyethylene) usually can be dissolved at elevated temperatures in aromatic hydrocarbons such as toluene orxylene, or in chlorinated solvents such as trichloroethane or trichlorobenzene.ProcessMonomerEthylene (ethene). The ingredient or monomer is ethylene (IUPAC name ethene), a gaseous hydrocarbon with the formula C2H4, which can be viewed as a pair of methylene groups(=CH 2) connected to each other. Because the catalysts are extremely reactive, the ethylene must be of high purity.