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It is the ethylene (IUPAC name: ethene) molecule (H 2 C=CH 2) with one fewer hydrogen atom. The name is also used for any compound containing that group, namely R−CH=CH 2 where R is any other group of atoms. An industrially important example is vinyl chloride, precursor to PVC, [3] a plastic commonly known as vinyl. Chessboard made from ...
The ingredient or monomer is ethylene (IUPAC name ethene), a gaseous hydrocarbon with the formula C 2 H 4, which can be viewed as a pair of methylene groups (− CH 2 −) connected to each other. Typical specifications for PE purity are <5 ppm for water, oxygen, and other alkenes contents.
The essential difference between the two is that in chain polymerization, monomers are added to the chain one at a time only, [18] such as in polystyrene, whereas in step-growth polymerization chains of monomers may combine with one another directly, [19] such as in polyester.
Epoxide monomers may be cross linked with themselves, or with the addition of a co-reactant, to form epoxy; BPA is the monomer precursor for polycarbonate; Terephthalic acid is a comonomer that, with ethylene glycol, forms polyethylene terephthalate. Dimethylsilicon dichloride is a monomer that, upon hydrolysis, gives polydimethylsiloxane.
To clarify, the polymer is named using the polymer class name followed by a colon and the name of the monomer, i.e., class name:monomer name. Thus on the left and right, respectively, are polyalkylene:vinyloxirane and polyether:vinyloxirane.
Vinyl chloride, also called vinyl chloride monomer (VCM), is exclusively used as a precursor to PVC. Due to its toxic nature, vinyl chloride is not found in other products. Poly(vinyl chloride) (PVC) is very stable, storable and not toxic. [2] Until 1974, vinyl chloride was used in aerosol spray propellant. [7]
Most polyolefin are made by treating the monomer with metal-containing catalysts. The reaction is highly exothermic. Traditionally, Ziegler-Natta catalysts are used. Named after the Nobelists Karl Ziegler and Giulio Natta, these catalysts are prepared by treating titanium chlorides with organoaluminium compounds, such as triethylaluminium.
Polymers can be classified in many ways. Polymers, strictly speaking, comprise most solid matter: minerals (i.e. most of the Earth's crust) are largely polymers, metals are 3-d polymers, organisms, living and dead, are composed largely of polymers and water. Often polymers are classified according to their origin: biopolymers; synthetic polymers