Mercaptans characteristics

The polysulfide base material contains 50—80% of the polyfunctional mercaptan, which is a clear, amber, sympy Hquid polymer with a viscosity at 25°C of 35, 000 Pa-s(= cP), an average mol wt of 4000, a pH range of 6—8, and a ntild, characteristic mercaptan odor. Fillers are added to extend, reinforce, harden, and color the base. They may iaclude siUca, calcium sulfate, ziac oxide, ziac sulfide [1314-98-3] alumina, titanium dioxide [13463-67-7] and calcium carbonate. The high shear strength of the Hquid polymer makes the compositions difficult to mix. The addition of limited amounts of diluents improves the mix without reduciag the set-mbber characteristics unduly, eg, dibutyl phthalate [84-74-2], tricresyl phosphate [1330-78-5], and tributyl citrate [77-94-1]. 

Observable Characteristics - Physical State (as shipped) Liquid Color Yellow to dark brown Odor Characteristic skunk-like mercaptan. 

Let us now discuss some of the characteristics of this quenching with mercaptans and disulfides. Interestingly, both sulfur derivatives are equally effective in inhibiting the photoreduction and are in fact interconverted during the reaction. The same equilibrium mixture of mercaptan and disulfide is obtained regardless of which was initially added to the reaction mixture. Furthermore, there appears to be no appreciable consumption of the sulfur compounds/64 When benzophenone is irradiated in the presence of isopropanol (OD) and mercaptan, isopropanol containing two deuterium atoms is isolated,... 

Figure 5.16 represents mass spectra of 1-chlorooctane and 2-chlorooctane. One can see that the base peak of m/z 91 in the first spectra is absent in the second one. The intensity of the m/z 105 ion peak (an analog of the cyclic ion for 2-chlorooctane) constitutes not 100%, but only 6% (Fig. 5.16b). Similar processes are characteristic for alkyl-mercaptanes (5-membered cycles) and alkylamines (6-membered cycles).

The secretion of the anal glands of skunks epitomizes mammalian defense secretions. Sulfur compovmds in the scent of striped skunk Mephitis mephitis) include rra 5-2-butene-l-thiol, 3-methyl-l-butanethiol (Andersen and Bernstein, 1975), rra 5-2-butenyl thioacetate, 3-methylbutanyl thioacetate, and 2-quinolinemethane thiol (Wood, 1990 Fig. 10.9). The thiols, once called mercaptans (because they captured mercury atoms), are like alcohols with a sulfur atom in place of the oxygen. In the striped skvmk, the thioacetates break down in water. They yield thiols, which have the more potent, characteristic skunk odor and linger for up to 2 weeks. In the spotted skunk, by contrast, the... 

The mercaptans are colourless liquids, mostly insoluble in water, possessing a characteristic disagreeable odour. 

Single-component adsorption equilibria on activated carbon of the n-alkanes Q-C4 and of the odorant tert-butyl mercaptan were measured at the operating conditions expected in a large-scale facility for adsorbed natural gas (ANG) storage. The experimental data were correlated successfully with the Adsorption Potential theory and collapsed into a single temperature-independent characteristic curve. The obtained isotherm model should prove to be very useful for predicting the adsorption capacity of an ANG storage tank and to size and optimize the operation of a carbon-based filter for ANG applications. 

The general kinetic characteristics of all of the butene reactions are very similar, and it should be further noted that none of them forms vinylic mercaptans. 

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