Initiators sulfonate

Roberts et al. [131,132] investigated the formation of sultones in the production of AOS. In the initial sulfonation stage, these include 1,2-, 1,3-, and 1-4-sultones. As indicated earlier, the 1,2 and 1,3 derivatives are easily hydrolyzed to produce sulfonates. The 1,4-sultone (8 sultone) is fairly resistant to saponification, and severe conditions are required for complete conversion to sulfonates. The presence, then, of 1,4-sultone is an indication of the degree of hydrolysis. 

Only the a-olefins are sulfonated commercially to make a-olefinsulfonate (AOS). The chemistry of a-olefin sulfonation is usually described in terms of three stages. The initial sulfonation reaction involves the formation of 3-sul-tones. This initial step is so fast as to be almost instant. Reaction of the initially formed B-sultones with more S03 is competitive with sulfonation of the olefin. This side reaction produces a byproduct believed to be a cyclic pyro-sulfonate ester, i.e., a pyrosultone ... 

The adsorption plateaus on this solid, determined with each of the surfactants (Table II) and the individual CMC values, were used to calculate the adsorption constants input in the model. Figure 3 compares the total adsorption (sulfonate + NP 30 EO) of the pseudo-binary system investigated as a function of the initial sulfonate fraction of the mixtures under two types of conditions (1) on the powder solid, batch testing with a solid/liquid ratio, S/L = 0.25 g/cc (2) in the porous medium made from the same solid, for which this solid ratio is much higher (S/L = 4.0 g/cc). 

Figure 4. Monomer concentration versus initial sulfonate fraction for two typical solid-liquid ratios.

The membrane permeate contains <10% of the initial sulfonate content and is treated in the central biological wastewater treatment plant. The entire process is operated continuously. 

Sevenich and Fritz [39] examined the sulfonation of resins for use in IC in some detail. Spherical microporous resin beads of 4%, 6.5% and 12% cross-linking were selected for their study. Initially, sulfonation of 4% cross-Unked resin... 

The PEM fuel cell was invented at General Electric (GE) in the early 1960s, through the work of Thomas Grubb and Leonard Niedrach. Initially, sulfonated polystyrene membranes were used as the solid electrolytes, but these were soon replaced by Nation membranes in 1966. The Nation membrane has proved to be superior in performance and durability, and it is still the most popular membrane in use today. 

In the naphthols 168 and 171, ring B is activated towards sulfonation by the attached hydroxyl group relative to the unsubstituted ring A consequently initial sulfonation always preferentially occurs in ring B. 

As in most electrophilic reactions, the abiUty to stabilize the positive charge generated by the initial addition strongly affects the relative rates. MX reacts faster than OX and PX because both methyl groups work in conjunction to stabilize the charge on the next-but-one carbon. Sulfonation was, at one time, used to separate MX from the other Cg aromatic isomers. MX reacts most rapidly to form the sulfonic acid which remains in the aqueous phase. The sulfonation reaction is reversible, and MX can be regenerated. 

Sodium Poly(4-styrene sulfonate). The sol—gel processing of TMOS in the presence of sodium poly-4-styrene sulfonate (NaPSS) has been used to synthesize inorganic—organic amorphous complexes (61). These sodium siUcate materials were then isotherm ally crystallized. The processing pH, with respect to the isoelectric point of amorphous siUca, was shown to influence the morphology of the initial gel stmctures. Using x-ray diffraction, the crystallization temperatures were monitored and were found to depend on these initial microstmctures. This was explained in terms of the electrostatic interaction between the evolving siUcate stmctures and the NaPSS prior to heat treatment at elevated temperatures. 

Sulfonation. Aniline reacts with sulfuric acid at high temperatures to form -aminoben2enesulfonic acid (sulfanilic acid [121 -57-3]). The initial product, aniline sulfate, rearranges to the ring-substituted sulfonic acid (40). If the para position is blocked, the (9-aminoben2enesulfonic acid derivative is isolated. Aminosulfonic acids of high purity have been prepared by sulfonating a mixture of the aromatic amine and sulfolane with sulfuric acid at 180-190°C (41). 

The history of the discovery of amino acids is closely related to advances ia analytical methods. Initially, quantitative and qualitative analysis depended exclusively upon crystallization from proteia hydrolysates. The quantitative precipitation of several basic amino acids including phosphotungstates, the separation of amino acid esters by vacuum distillation, and precipitation by sulfonic acid derivatives were developed successively duriag the last century. 

Delignification Chemistty. The chemical mechanism of sulfite delignification is not fully understood. However, the chemistry of model compounds has been studied extensively, and attempts have been made to correlate the results with observations on the rates and conditions of delignification (61). The initial reaction is sulfonation of the aUphatic side chain, which occurs almost exclusively at the a-carbon by a nucleophilic substitution. The substitution displaces either a hydroxy or alkoxy group ... 

Although soaps have many physical properties in common with the broader class of surfactants, they also have several distinguishing factors. First, soaps are most often derived direcdy from natural sources of fats and oils (see Fats and fatty oils). Fats and oils are triglycerides, ie, molecules comprised of a glycerol backbone and three ester-linked fatty oils. Other synthetic surfactants may use fats and oils or petrochemicals as initial building blocks, but generally require additional chemical manipulations such as sulfonation, esterification, sulfation, and amidation. 

Polymerization Solvent. Sulfolane can be used alone or in combination with a cosolvent as a polymerization solvent for polyureas, polysulfones, polysUoxanes, polyether polyols, polybenzimidazoles, polyphenylene ethers, poly(l,4-benzamide) (poly(imino-l,4-phenylenecarbonyl)), sUylated poly(amides), poly(arylene ether ketones), polythioamides, and poly(vinylnaphthalene/fumaronitrile) initiated by laser (134—144). Advantages of using sulfolane as a polymerization solvent include increased polymerization rate, ease of polymer purification, better solubilizing characteristics, and improved thermal stabUity. The increased polymerization rate has been attributed not only to an increase in the reaction temperature because of the higher boiling point of sulfolane, but also to a decrease in the activation energy of polymerization as a result of the contribution from the sulfonic group of the solvent. 

Amide-Based Sulfonic Acids. The most important amide-based sulfonic acids are the alkenylarnidoalkanesulfoiiic acids. These materials have been extensively described ia the Hterature. A variety of examples are given ia Table 5. Acrylarnidoalkanesulfoiiic acids are typically prepared usiag technology originally disclosed by Lubrizol Corporation ia 1970 (80). The chemistry iavolves an initial reaction of an olefin, which contains at least one aHyhc proton, with an acyl hydrogen sulfate source, to produce a sulfonated intermediate. This intermediate subsequendy reacts with water, acrylonitrile, and sulfuric acid. 

Thermal Stability. Dimethyl sulfoxide decomposes slowly at 189°C to a mixture of products that includes methanethiol, formaldehyde, water, bis(methylthio)methane, dimethyl disulfide, dimethyl sulfone, and dimethyl sulfide. The decomposition is accelerated by acids, glycols, or amides (30). This product mixture suggests a sequence in which DMSO initially undergoes a Pummerer reaction to give (methylthio)methano1, which is labile and reacts according to equations 1—3. Disproportionation (eq. 4) also occurs to a small extent ... 

Orga.nic Chemistry. The organic chemistry of sulfur dioxide, particularly as it relates to food appHcations, has been discussed (246). Although no reaction takes place with saturated hydrocarbons at moderate temperatures, the simultaneous passage of sulfur dioxide and oxygen into an alkane in the presence of a free-radical initiator or ultraviolet light affords a sulfonic acid such as hexanesulfonic acid [13595-73-8]. This is the so-called sulfoxidation reaction (247) ... 

Alkyl sulfonic acids are prepared by the oxidation of thiols (36,37). This reaction is not quite as simple as would initially appear, because the reaction does not readily go to completion. The use of strong oxidants can result in the complete oxidation of the thiol to carbon dioxide, water, and sulfur dioxide. 

Methane sulfonic acid, trifluoroacetic acid, hydrogen iodide, and other Brmnsted acids can faciUtate 3 -acetoxy displacement (87,173). Displacement yields can also be enhanced by the addition of inorganic salts such as potassium thiocyanate and potassium iodide (174). Because initial displacement of the acetoxy by the added salt does not appear to occur, the role of these added salts is not clear. Under nonaqueous conditions, boron trifluoride complexes of ethers, alcohols, and acids also faciUtate displacement (87,175). 

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