Polymerization benzene with sulfur

The high-temperature condensation of aromatic halides (diphenylsulfide, thian-threne, diphenyldisulfide, thiophenol and direct reactions of benzene with sulfur) in the presence of aluminium chloride was examined by Sergeyev et al. [98]. The reaction of 1,4-dichlorobenzene or 1,4-dibromobenzene with sodium sulfide at 195 °C in N-methylpyrrolidone (NMP) has been studied under normal atmospheric pressure, the kinetic of polymerization was found to be of second order. The same reaction in NMP was revised by Russian authors [99]. The polymerization of diphenyldisulfide produced PPS when stoichiometric amounts of diphenyldisulfide and antimoniumpentachloride were used in nitrobenzene at 20 °C. The S-S bond cleavage is catalyzed by the Lewis acid and the authors claim to have obtained an identic product compared with the commercial one with a molecular weight >1000 [100]. 

A recent paper describes the reaction of 2-pyridone with sulfur dichloride when these are boiled in benzene for a week the 5,5 -dipyridyl sulfide (80) is formed in 13% yield. The structure of 80 was confirmed by its ultraviolet and nuclear magnetic resonance (NMR) spectra.173 3-Hydroxypyridine gives a poorly defined and apparently high polymeric substance under these conditions, whereas 4-pyridone is said not to react. 

Paushkin and Topchiev also used H3P()4-BF3 at room temperature to alkylate benzene with olefins (287,402). For alkylation of benzene with alcohols, temperatures of 90-97° and a feed mole ratio of 0.5 alcohol 1.0 benzene 0.5 catalyst were recommended (394). In a recent study (400a) these authors supplemented their previously published views (396) concerning the properties of boron fluoride complexes with phosphoric acid, alcohols, and sulfuric acid as catalysts. Data on the electroconductivity of these catalysts was correlated with their activity in alkylation of isobutane and it was concluded (400a) that the acid ion concentration did not affect the alkylation or polymerization reactions over these catalysts, and therefore the carbonium ion mechanism was not applicable. 

Derivation Benzene is alkylated with dodecene, to which it attaches itself in any secondary position the resulting dodecylbenzene is sulfonated with sulfuric acid and neutralized with caustic soda. For ABS (branched-chain alkyl) the dodecene is usually a propylene tetramer, made by catalytic polymerization of propylene. For LAS (straight-chain alkyl), the dodecene may be removed from kerosene or crudes by molecular sieve, may be formed by Ziegler polymerization of ethylene, or by cracking wax paraffins to a-olefins. 

Styrene is obtained almost exclusively from the catalytic dehydrogenation of ethyl benzene (600°C, metal oxide). Ethyl benzene is obtained by a Friedel-Crafts reaction of benzene with ethylene. The separation of the styrene from the tetrafunctional, and therefore cross-linkable, divinyl benzene is important. In order to prevent premature polymerization, sulfur or dinitrophenols are added before distillation and t-butyl catechol is added before storing. 

The only report of polymeric material from benzene and sulfur with A1C1 ... 

Ryton PPS was seriously degraded when treated with AlCl in TCB at a high temperature and only a small amount of polymeric material was recovered (Table 6). Both the content of sulfur and hydrogen had changed to be within the ranges of the polymers from benzene and sulfur. The molecular weights had decreased to the range of the experimental polymers. 

Phenyl sulfide, thianthrene, and phenyl disulfide had been formed at 41 C before appearance of the colored complex. The amount of each compound peaked at different times and temperatures. Phenyl sulfide in the first major compound formed but is soon displaced by thianthrene at temperatures above 90 C. The rather large amounts of thianthrene could even have been larger, however, as part of it crystallized from the samples and did not completely redissolve. Phenylthiothianthrene was the major heavy component, the heaviest to pass through the GLC column. Thiophenol, phenyl disulfide, and phenyl trisulfide were present in small amounts throughout most of the polymerization. Bis(phenylthio)benzene was formed in small amounts during the polymerization. This is a novel product of the reaction between benzene and sulfur with AlCl and was not detected among the products in Table 1. This compound can be converted easily into phenylthiothianthrene. 

The major intermediate compound in the polymerization of benzene and sulfur is thianthrene and the same polymer can be made with thianthrene as the starting material. Therefore, the conclusion can only be that the polymer consists of thianthrene units connected by sulfide linkages with an... 

Allegations that poly(phenylene sulfide) was originally prepared by the reaction of benzene and sulfur with AlCl are a result of creative reading of the literature. Formation of high molecular weight poly(arylene sulfides) in the presence of AlCl is highly unlikely because the latter catalyzes both polymerization and degradation reactions. 

Thiopolyurethanes (134) with sulfur in side chain ([ ] 0.1-0.3 dL/g) prepared by solution (benzene) polymerization of the diol (129) with diisocyanates (135), HDI (135a), MDI (135b), or 2,4-TDI (2,4-tolnene diisocyanate, 2,4-tolylene diisocyanate, 2,4-diisocyanatotoluene, etc) [584-84-9] (135c), were used as the polymeric intermediates for the synthesis of these polymers. The benzyl groups were successfully removed from polymer (134a) with sodium in a mixed solvent of liquid ammonium and -propylamine [107-10-8], giving polymer (136). 

Sulfur vaporizes at 444.6°C. The element, particularly in its orthorhombic Ss form, is insoluble in water but dissolves in carbon disulfide, anhydrous liquid ammonia, and methylene iodide. It is moderately soluble in benzene, toluene, chloroform, and acetone, solubility increasing with temperature. Solid polymeric sulfur is practically insoluble in all solvents. 

Neither the thermal nor the cobalt-catalyzed decomposition of 3-butene-2-hydroperoxide in benzene at 100 °C. produced any acetaldehyde or propionaldehyde. In the presence of a trace of sulfuric acid, a small amount of acetaldehyde along with a large number of other products were produced on mixing. Furthermore, on heating at 100°C., polymerization is apparently the major reaction no volatile products were detected, and only a slight increase in acetaldehyde was observed. Pyrolysis of a benzene or carbon tetrachloride solution at 200°C. in the injection block of the gas chromatograph gave no acetaldehyde or propionaldehyde, and none was detected in any experiments conducted in methanol. 

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