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If unsaturated esters are copolymerized with ethylene, either the alcohol moiety may be in the polymer backbone (as it is the case in ethylene-vinyl acetate copolymer) or of the acid moiety (e. g. in ethylene-ethyl acrylate copolymer). Ethylene-vinyl acetate copolymers are prepared similarly to LD-PE by high pressure polymerization. The ...
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).
For example, for the polymerization of ethylene, 93.6 kJ of energy are released per mole of monomer. [8] The manner in which polymerization is conducted is a highly evolved technology. Methods include emulsion polymerization, solution polymerization, suspension polymerization, and precipitation polymerization.
The mechanism for the polymerization process is the subject of much research, the central question being the structure of the active species, which is assumed to be an organochromium compound. [2] Robert L. Banks and J. Paul Hogan, both at Phillips Petroleum, filed the first patents on the Phillips catalyst in 1953. Four years later, the ...
Usually Ziegler catalysts refer to titanium-based systems for conversions of ethylene and Ziegler–Natta catalysts refer to systems for conversions of propylene. Also, in the 1960s, BASF developed a gas-phase, mechanically-stirred polymerization process for making polypropylene. In that process, the particle bed in the reactor was either not ...
Industrial production of HDPE from ethylene happens through either Ziegler-Natta polymerization or the Phillips slurry process. The Ziegler-Natta method uses a combination of catalysts, including titanium tetrachloride, in contact with gaseous ethylene to precipitate high-density polyethylene. [17]
Ethylene vinyl alcohol (EVOH) is a formal copolymer of ethylene and vinyl alcohol. Because the latter monomer mainly exists as its tautomer acetaldehyde , the copolymer is prepared by polymerization of ethylene and vinyl acetate to give the ethylene vinyl acetate (EVA) copolymer followed by hydrolysis.
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.