Acetylene physical properties

Normally absent or in trace amounts in crude oil, products of conversion processes such as diolefins, acetylenes, etc., are encountered. Table 1.4 gives the physical properties of some of them. Noteworthy is 1-3 butadienerC ( l)... 

Butynediol. Butynediol, 2-butyne-l,4-diol, [110-65-6] was first synthesized in 1906 by reaction of acetylene bis(magnesium bromide) with paraformaldehyde (43). It is available commercially as a crystalline soHd or a 35% aqueous solution manufactured by ethynylation of formaldehyde. Physical properties are Hsted in Table 2. 

Table 5 Hsts the principal commercially available acetylenic alcohols and glycols Tables 6 and 7 Hst the physical properties of acetylenic alcohols and glycols, respectively.

Vlayl fluoride [75-02-5] (VF) (fluoroethene) is a colorless gas at ambient conditions. It was first prepared by reaction of l,l-difluoro-2-bromoethane [359-07-9] with ziac (1). Most approaches to vinyl fluoride synthesis have employed reactions of acetylene [74-86-2] with hydrogen fluoride (HF) either directly (2—5) or utilizing catalysts (3,6—10). Other routes have iavolved ethylene [74-85-1] and HF (11), pyrolysis of 1,1-difluoroethane [624-72-6] (12,13) and fluorochloroethanes (14—18), reaction of 1,1-difluoroethane with acetylene (19,20), and halogen exchange of vinyl chloride [75-01-4] with HF (21—23). Physical properties of vinyl fluoride are given ia Table 1. 

Because it was not possible to explain the differences in the effectiveness of hydrogen as compared to other gases on the basis of differences in their physical properties, ie, thermal conductivity, diffusivity, or heat capacity differences, their chemical properties were explored. To differentiate between the hydrogen atoms in the C2H2 molecules and those injected as the quench, deuterium gas was used as the quench. The data showed that although 90% of the acetylene was recovered, over 99% of the acetylene molecules had exchanged atoms with the deuterium quench to form C2HD and... 

The use of the Hammett equation has also been extended to several new types of applications. Since these are not germane to the subject matter of the present chapter, we wiU simply mention work on applications to ethylenic and acetylenic compounds the various applications to physical properties, such as infrared frequencies and intensities, ultraviolet spectra, polarographic half-wave potentials, dipole moments,NMR and NQR spectra,and solubility data and applications to preparative data and biological activity. 

Acetylene is a simple asphyxiant and anaesthetic. Pure acetylene is a colourless, highly flammable gas with an ethereal odour. Material of commercial purity has an odour of garlic. Its physical properties are shown in Table 8.4. 

North American producers of, 7 129t physical properties of, 7.T15-117 5 29t production from acetaldehyde, 7 102, 111 production from acetylene, 7 219 production from carbon monoxide, 5 4-5 production of, 76 299 24 265... 

Acetylenic glycols, 1 249-250 physical properties of, l 250t N-Acetylethanolamine, physical properties of, 2 124t... 

Dibromobutane acetylene-derived, 1 242 physical properties of, 4 350t... 

Ethyl vinyl ether, 1 254, 258 derivation from ethanol, 10 557 physical properties of, l 255t Ethynylation, acetylene, 1 181, 231-249 Etretinate, 25 790 Etridiazole, 23 629... 

Solid state NMR has been used to study polymers of various classes over the past several years. In particular, the technique has been used to study curing reactions in epoxies (12). polyimides (1), and acetylenic terminated sulfones (13). The ability to observe the evolution of the carbons of the reacting species has been clearly shown to provide valuable information which has been difficult or impossible to obtain with other techniques. The use of 13C solid state NMR techniques is essential for the understanding of curing reactions in high temperature polymers in order to be able to correlate the reaction chemistry with the structural and resulting physical properties. 

Little is known as yet of the chemistry of the monocyclic 1,2,3-triazines. The only reactions that have been reported are hydrolysis to substituted butane-1,3-diones, photolytic decomposition to acetylenes, nitriles, and nitrogen, and high temperature (250°) thermolysis, which leads to loss of nitrogen and formation of the corresponding diarylindenone imines. The structures of the latter compounds were confirmed on the basis of their physical properties and by hydrolysis to the corresponding known diarylindenones. ... 

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