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Polymerization ethyne

Wang, yanni, Zhang, Zhikun and Cui, Zuolin (1995). The catalysis of nano particles in the reaction of ethyne polymerization. Jour, of Catalysis, 16(4) 304-307 (in Chinese). [Pg.351]

Ethyne polymerizes if passed through a hot tube to produce some benzene ... [Pg.12]

COT is prepared by the polymerization of ethyne at moderate temperature and pressure in the presence of nickel salts. The molecule is non-planar and behaves as a typical cyclic olefin, having no aromatic properties. It may be catalytically hydrogenated to cyclo-octene, but with Zn and dil. sulphuric acid gives 1,3,6-cyclooclairiene. It reacts with maleic anhydride to give an adduct, m.p. 166 C, derived from the isomeric structure bicyclo-4,2,0-octa-2,4,7-triene(I) ... [Pg.122]

Acetylene (ethyne), C2H2, can be polymerized, (a) Draw the Lewis structure for acetylene and draw a Lewis structure for the polymer that results when acetylene is polymerized. The polymer has formula (CH), where n is large, (b) Consider the polymers polyacetylene and polyethylene. The latter has the formula (CH2)W and is an insulating material (plastic wrap is made of polyethylene), whereas polyacetylene is a darkly colored material that can conduct electricity when properly treated. On the basis of your answer to part (a), suggest an explanation for the difference in the two polymers. [Pg.256]

The same arsenal of preparative methods has been applied successfully for the corresponding dinuclear derivatives of ethyne HC CH and dialkynes HC C-X-C CH, where X can be virtually any spacer unit.50-52,54 55 57 61 62 71 76-83 As mentioned in the introduction to this chapter, ethyne is readily converted into polymeric explosive AuC=CAu and its complexes (L)AuC=CAu(L), of which the families with L = R3P84 and L = RNC are particularly large (Chapter 7). With the unit X in (L)AuC=CXC=CAu(L) being an alkylidene spacer, flexible complexes are obtained, while with alkenylidene, alkynylidene, or arylidene units,57 rigid molecules (L)AuC=CXC=GA11(L) are generated. Specific examples are presented below in the context with the structural patterns of extended systems. [Pg.257]

Some [MX]+ ions enter into reactions in which the ligand X and the reacting molecule become chemically bonded. Polymerization processes have been observed involving the [MC4H4]+ ions (147). The butadiene complex ions [MC4H4]+ of Co and Ni are unreactive to ethyne but the Fe, Ru, and Rh ions react to yield benzene and the bare metal ion. The [MC4H4]+ complex ions of Os+, Ir+, and Pt+ react with ethyne to form the MC4I I4 + ions that probably correspond to the benzyne complexes previously observed for platinum (126). [Pg.387]

Ethynes are industrially used as a starting material for polymers, e.g. vinyl flooring, plastic piping. Teflon and acrylics. Polymers are large molecules, which are prepared hy linking many small monomers. Polyvinyl chloride, also commonly known as PVC, is a polymer produced from the polymerization of vinyl chloride. [Pg.110]

Fig. 3. Raman spectra of ethyne (in polymerized form as a long-chain polyacetylene) on (A) Rh/Al203 and (B) a gold electrode. [(A) Reprinted with permission from Ref. 94. Copyright 1985 American Chemical Society (B) reprinted with permission from Ref. 83. Copyright 1985 American Chemical Society.]... Fig. 3. Raman spectra of ethyne (in polymerized form as a long-chain polyacetylene) on (A) Rh/Al203 and (B) a gold electrode. [(A) Reprinted with permission from Ref. 94. Copyright 1985 American Chemical Society (B) reprinted with permission from Ref. 83. Copyright 1985 American Chemical Society.]...
Of the coinage metals, finely divided copper shows evidence of strong rehybridization of adsorbed ethyne, such as occurs with transition metals Ni, Pd, Pt, and Rh, which have unfilled d orbitals. On the other hand, SER spectra from ethyne on cold-deposited silver at low temperatures show only moderately perturbed 7T-bonded species. There is SERS evidence of polymerization to long-chain polyenes on silver and gold electrodes at room temperature. [Pg.202]

Cyclooctatetraene can be prepared readily by polymerization of ethyne in the presence of nickel cyanide ... [Pg.1085]

Wang, yanni and Zhang, Zhikun (1995). Growth scheme of polymerized ethyne on the surface of nano copper particles. Functional Materials, supplement issue, 501-502 (in Chinese). [Pg.351]

Applications to polymer chemistry have also been proposed. Interestingly. the adhesion toward itself. Al or stainless steel, of polythene or TeHon with epoxyresins adhesives is considerably improved by a glow discharge polymerization of methane (or etheiie. ethyne) on the polymer surface, CH4 giving the best results (33). Such a modification of polymer surfaces has also received attention within the scope of modifying poly mer membrane compatibility with blood for medical applications. Various o nic compounds (even CH4 > have been studied in this context, where an ultrathin layer (< 1000 is sufficient to alter blood compatibility 134). [Pg.251]

A second problem is that the formation of defects that lower the emission efficiency is intrinsic in the polymerization process due to nonregular coupling of the quinodimethane intermediates, as illustrated in Scheme 6.5 for the Gilch synthesis. This has been demonstrated by NMR studies on a 13C-labelled PPV derivative, in which the ethyne and ethane moieties could be detected in 1.5-2.2% amount [38-40], By appropriate choice of substituents the levels of these defects can be minimized to obtain high-efficiency polymers [41]. [Pg.219]


See other pages where Polymerization ethyne is mentioned: [Pg.196]    [Pg.285]    [Pg.196]    [Pg.285]    [Pg.169]    [Pg.259]    [Pg.419]    [Pg.420]    [Pg.420]    [Pg.421]    [Pg.890]    [Pg.941]    [Pg.61]    [Pg.135]    [Pg.191]    [Pg.201]    [Pg.202]    [Pg.221]    [Pg.972]    [Pg.288]    [Pg.162]    [Pg.171]    [Pg.212]    [Pg.208]    [Pg.218]    [Pg.2107]    [Pg.972]    [Pg.135]    [Pg.332]    [Pg.61]    [Pg.9]    [Pg.333]   
See also in sourсe #XX -- [ Pg.882 ]




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