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Polyethylene was first synthesized by the German chemist Hans von Pechmann, who prepared it by accident in 1898 while investigating diazomethane. [12] [a] [13] [b] When his colleagues Eugen Bamberger and Friedrich Tschirner characterized the white, waxy substance that he had created, they recognized that it contained long −CH 2 − chains and termed it polymethylene.
Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene. It was the first grade of polyethylene, produced in 1933 by John C. Swallow and M.W Perrin who were working for Imperial Chemical Industries (ICI) using a high pressure process via free radical polymerization. [1] Its manufacture employs the same method today.
HDPE is known for its high strength-to-density ratio. [4] The density of HDPE ranges from 930 to 970 kg/m 3. [5] Although the density of HDPE is only marginally higher than that of low-density polyethylene, HDPE has little branching, giving it stronger intermolecular forces and tensile strength (38 MPa versus 21 MPa) than LDPE. [6]
Polyethylene + acrylonitrile butadiene styrene (PE + ABS): a slippery blend of PE and ABS used in low-duty dry bearings Polymethyl methacrylate (PMMA) ( acrylic ): contact lenses (of the original "hard" variety), glazing (best known in this form by its various trade names around the world; e.g. Perspex , Plexiglas, and Oroglas), fluorescent ...
Polyethylene terephthalate is produced largely from purified terephthalic acid (PTA), as well as to a lesser extent from (mono-)ethylene glycol (MEG) and dimethyl terephthalate (DMT). [ 41 ] [ 5 ] As of 2022, ethylene glycol is made from ethene found in natural gas , while terephthalic acid comes from p-xylene made from crude oil .
Commodity plastics or commodity polymers are plastics produced in high volumes for applications such as packaging, food containers, and household products, including both disposable products and durable goods. In contrast to engineering plastics, commodity plastics tend to be inexpensive to produce and exhibit relatively weak mechanical properties.
Today the Braskem industrial unit has an annual production capacity of 200 000 tonne of Green Polyethylene. Green PE has the same properties, performance, and application versatility as fossil-based polyethylene, which makes it a drop-in replacement in the plastic production chain.
The plastics industry manufactures polymer materials—commonly called plastics—and offers services in plastics important to a range of industries, including packaging, building and construction, electronics, aerospace, manufacturing and transportation.