Acetylene containers

Poly(phenylquinoxalines) containing acetylene groups in main chains of macromolecules 99MI28. 

In stimulation fluids containing concentrated HCl, the partial substitution of water by alcohols such as methanol, ethanol, and glycerol increases the corrosivity of the acid fluids and reduces the efficiency of the corrosion inhibitors [1148]. This effect is especially important for fatty amine-based inhibitors. For products containing acetylenic-type inhibitors the detrimental effect is less important and a weight loss may be maintained within acceptable limits using slightly higher, but still reasonable, levels of inhibitor. 

An interesting reaction was studied by A. Schwartz (1997) UV irradiation of phosphate solutions containing acetylene gave vinylphosphonic acid. 

Class 1 Content (Liquid, Gas or Vapor) Atmospheres containing acetylene. Historical Approach Group A Alternate Approach Group lie... 

Ketones containing acetylenic bonds were reduced selectively at the triple bond by catalytic hydrogenation. Over 5% palladium on calcium carbonate in pyridine (which decreases the activity of the catalyst) 17-ethynyltestosterone was reduced in 95% yield to 17-vinyltestosterone, while over palladium on charcoal in dioxane 80% of 17-ethyltestosterone was obtained the carbonyl in position 3 and the conjugated 4,5-double bond remained intact [386]. 

Examples of the polymerizations of heteroatom-containing acetylenes have been increasing. The heteroatoms include Si, halogens, O, S, and N. Especially, Si and F endow the polymers with unique properties and functions, and... 

Jd] or [92] (7). All other new trirhodium clusters contain acetylene ligands and have either the formula (GpRh)3(RG=GR) with the basic structure 99 or (GpRh)3-(RG=GR)(GO) with the basic structures [70(9] or [707], They are formed from... 

There is a seemingly endless variety of fatty acids, but only a few of them predominate in any single organism. Most fatty acid chains contain an even number of carbon atoms. In higher plants the C16 palmitic acid and the C18 unsaturated oleic and linoleic acids predominate. The C18 saturated stearic acid is almost absent from plants and C20 to C24 acids are rarely present except in the outer cuticle of leaves. Certain plants contain unusual fatty acids which may be characteristic of a taxonomic group. For example, the Compositae (daisy family) contain acetylenic fatty acids and the castor bean contains the hydroxy fatty acid ricinoleic acid. 

Other algal carotenoids contain acetylenic triple bonds. For example, alloxanthin has the following structure at both ends of the symmetric molecule. The symmetric carotenoids canthaxanthin and astaxan-thin have oxo groups at both ends ... 

Cathode may also contain acetylene/carbon black to absorb electrolyte... 

Ethyl Alcohol.—In an atmosphere of ethyl-alcohol vapors, M. Quet5 and Perrot 6 obtained, besides some carbon, a substance which exploded on being heated, the chemical nature of which they were unable to determine. The liquid became acid but Perrot found that no water was formed in the decomposition of the alcohol he was also unable to prove the presence of carbonic acid gas. Melly 7 and Lommel8 made similar experiments, the latter employed a Holtz machine. The gas escaping in the decomposition of the alcohol probably contains acetylene and ethylene. 

Naphthalene.—Wilde2 also investigated the behavior of naphthalene vapor under reduced pressure when subjected to-the action of the induction spark. He obtained a gas mixture containing acetylene. 

The objectives of this study were to extend these synthetic methods to the preparation of low molecular weight, hydroxy-terminated polymers containing acetylenic bonds and evaluating these prepolymers in castable solid propellant formulations. Since 2-butyne-l,4-diol was commercially available, the formation of polyacetals from this glycol seemed to be an attractive route to the desired polymers. It was believed that the rigid triple bond would inhibit the cyclic acetal formation observed by the earlier workers with the lower members of the saturated glycol series. Thus, in an acetal interchange reaction a linear polymer (I) should be favored over the cyclic acetal (II) ... 

Mesogen-containing acetylene monomers, (II), were prepared by Tang [2] and polymerized into polyacetylenes, (III). These monomers had excellent tracta-bility typically associated with polymers having flexible backbones. 

Reaction of acetylenic derivatives of the elements of group 14 with triorganoboranes gives products of 1,1-organoboration [eq. (I)].1 At the same time, allylic boranes react with triple bonds by 1,2-addition mechanism through a six-membered transition state [eq. (2)].2 Therefore two different reaction pathways may be expected for interaction of A113B with Si-, Ge- and Sn-containing acetylenes. 

Among silicon-containing acetylenes, 3-(trimethylsilyl)-l-octyne and its homologs are converted to high-molecular-weight polymers36 (Table 11). The MoCls-cocatalyst and Mo(CO)6—CC —hv systems afford the highest MW s. On the other hand, 1-silyl-acetylenes such as l-(trimethylsilyl)acetylene and l-(dimethylphenylsilyl)acetylene afford partly toluene-insoluble polymers 34,35), and Mn of the soluble fractions is no more than ca. 1 x 104. 

Bromine-containing disubstituted acetylenes [BrC = C(CH2)4Br 44 ) BrC = CPh48 ] also polymerize with MoCls-cocatalyst and Mo(CO)6 —CC14—hv. However, their Mn ( 1 x 104) are not as high as those of chlorine-containing acetylenes. W catalysts exhibit slight activity toward these monomers. 

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