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Polyethylene absorbs almost no water; the gas and water vapour permeability (only polar gases) is lower than for most plastics. Oxygen, carbon dioxide and flavorings, on the other hand, can pass it easily. Polyethylene burns slowly with a blue flame having a yellow tip and gives off an odour of paraffin (similar to candle flame). The material ...
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]
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 ...
Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula C 2 H 4 or H 2 C=CH 2. It is a colourless, flammable gas with a faint "sweet and musky " odour when pure. [ 7 ] It is the simplest alkene (a hydrocarbon with carbon–carbon double bonds ).
The degradation of polyethylene occurs by random scission—a random breakage of the bonds that hold the atoms of the polymer together. When heated above 450 °C, polyethylene degrades to form a mixture of hydrocarbons. In the case of chain-end scission, monomers are released and this process is referred to as unzipping or depolymerization ...
Vinyl polymers are subject of several structural variations, which greatly expands the range of polymers and their applications. With the exception of polyethylene, vinyl polymers can arise from head-to-tail linking of monomers, head-to-head combined with tail-to-tail, or a mixture of those two patterns. Additionally the substituted carbon center in such polymers is stereogenic (a "chiral center")
Ethylene gas (H 2 C=CH 2) is the monomer for polyethylene. Other modified ethylene derivatives include: tetrafluoroethylene (F 2 C=CF 2) which leads to Teflon; vinyl chloride (H 2 C=CHCl) which leads to PVC; styrene (C 6 H 5 CH=CH 2) which leads to polystyrene; Epoxide monomers may be cross linked with themselves, or with the addition of a co ...
During polymerization, a polymer spends most of its time in increasing its chain length, or propagating. After the radical initiator is formed, it attacks a monomer (Figure 11). [8] In an ethene monomer, one electron pair is held securely between the two carbons in a sigma bond. The other is more loosely held in a pi bond. The free radical uses ...