Cellulose sulfonate

The most frequently synthesized and used cellulose sulfonates are the p-toluenesulfonates (tosylates), methanesulfo-nates (mesylates), p-bromobenzenesulfonates (brosylates), and ttifluoromethanesulfonates (Inflates). The synthesis of sulfonates through simple esterification of the -OH groups of cellulose with the corresponding sulfonic acid chlorides or anhydride is a way to attach nucleofuge groups to... 

Siegmund G., Klemm D., Cellulose Cellulose sulfonates preparation, properties, subsequent reactions, Polym. News, 27, 2002, 84-90. 

Various modified celluloses can be prepared from cellulose by introducing different functional groups. For example, carboxymethyl cellulose (or CMC) is prepared from cellulose by introducing carboxymethyl group. Cellulose xanthate (or CX) is prepared from cellulose by introducing dithiocarbonate radical [1]. Sulfonated cellulose sulfonate and ethoxyl cellulose are called CSE and CEH, respectively, for short. The stmctures of CMC, CX, CSE, and CEH can be seen as follows ... 

Because of its historical importance cellulose nitrate has traditionally dominated the content of articles devoted to inorganic esters of cellulose. While not understating the importance of cellulose nitrate, this report emphasizes the value of other inorganic esters of cellulose, including cellulose phosphate, cellulose sulfate, and cellulose sulfonates. 

Inorganic esters of cellulose include all esters where the atoms linked directly to the cellulosic oxygens are non-carbon, for examples, cellulose nitrate, cellulose sulfate, cellulose sulfonate, and cellulose phosphate. 

Sulfur-Containing Esters of Cellulose. Cellulose sulfate and cellulose sulfonates are examples of sulfur-containing esters of cellulose. The sulfur is linked directly to an oxygen atom contained within an anhydroglucose unit of cellulose (see Fig. 3). 

Cellulose Sulfonates. Cellulose sulfonates are inorganic esters of cellulose and sulfonic acids in which there is a sulfur-oxygen bond formed to link the cellulose and sulfonic acid moieties. Figure 4 depicts the three most common cellulose sulfonates described in the literature, cellulose methanesulfonate (mesylate) (4), cellulose toluenesulfonate (tosylate) (5), and cellulose dansylate (6) (22-25). Cellulose tosylate is the most commonly described cellulose sulfonate in the literature. Cellulose sulfonates are typically prepared in a homogeneous process by dissolving cellulose in a dimethylacetamide/lithium chloride (DMAc/LiCl) mixture and reacting the cellulose with sulfonylchloride in the presence of triethylamine (Fig. 5) (25). Cellulose sulfonates can also be prepared in situ for use as reactive intermediates (26,27). The use of cellulose tosylate as a reactive intermediate is be discussed in more detail later in this report. 

Solubility. Cellulose sulfate and cellulose phosphate can be either water-soluble or water-swellable depending on the conditions used during preparation vide supra). Cellulose nitrate and some cellulose sulfonates are generally more hydrophobic and are typically soluble in organic solvents. In general, the level of esterification of cellulose directly impacts the solubility of the product in various solvents and solvent blends. 

SynthGtiC IntGrnriGdiatGS. Cellulose sulfonates have been evaluated as S5mthetic intermediates (27,46-49). Cellulose tosylate activates the C6 hydroxyl for substitution with various nucleophiles (eq. 2 where Nu = Cl , Ns", NH2—(CH2)m NH2, or other nucleophiles). 

Additionally, cellulose sulfonates can also function as a protecting group to prevent reaction of the C6 hydroxyl during esterification reactions (Fig. 8). Cellulose tosylates with degrees of substitution from 0.38 to 2.30 have been reported. Although an effective synthetic tool, the expense of organic solvents utilized and the cost and corrosive nature of tosyl chloride have limited the use of this methodology on a commercial scale. 

Abstract The polymerization process in a solution was examined by SAXS and cryo-TEM in the case of chemical polymerization of pyrrole in aqueous solution using sodium cellulose sulfonate (SCS) and FeCls as oxidizing agents. Observations with SAXS and cryo-TEM indicated the formation of micelle of SCS in SCS + water system. By adding FeCls in the solution, large spherical aggregates... 

Poly(vinyl acetate) emulsions can be made with a surfactant alone or with a protective coUoid alone, but the usual practice is to use a combination of the two. Normally, up to 3 wt % stabilizers may be included in the recipe, but when water sensitivity or tack of the wet film is desired, as in some adhesives, more may be included. The most commonly used surfactants are the anionic sulfates and sulfonates, but cationic emulsifiers and nonionics are also suitable. Indeed, some emulsion compounding formulas require the use of cationic or nonionic surfactants for stable formulations. The most commonly used protective coUoids are poly(vinyl alcohol) and hydroxyethyl cellulose, but there are many others, natural and synthetic, which are usable if not preferable for a given appHcation. 

Some commercial durable antistatic finishes have been Hsted in Table 3 (98). Early patents suggest that amino resins (qv) can impart both antisHp and antistatic properties to nylon, acryUc, and polyester fabrics. CycHc polyurethanes, water-soluble amine salts cross-linked with styrene, and water-soluble amine salts of sulfonated polystyrene have been claimed to confer durable antistatic protection. Later patents included dibydroxyethyl sulfone [2580-77-0] hydroxyalkylated cellulose or starch, poly(vinyl alcohol) [9002-86-2] cross-linked with dimethylolethylene urea, chlorotria2ine derivatives, and epoxy-based products. Other patents claim the use of various acryUc polymers and copolymers. Essentially, durable antistats are polyelectrolytes, and the majority of usehil products involve variations of cross-linked polyamines containing polyethoxy segments (92,99—101). 

Dispersion Technology. Substantial advancements in dispersion technology have been made since the initial introduction in 1923 of disperse dyes in paste form for cellulose acetate. Dyes were dissolved in sulfonated fatty acids such as sulforicinoleic acid [36634-48-7] (SRA),... 

Zinc chloride is a Lewis acid catalyst that promotes cellulose esterification. However, because of the large quantities required, this type of catalyst would be uneconomical for commercial use. Other compounds such as titanium alkoxides, eg, tetrabutoxytitanium (80), sulfate salts containing cadmium, aluminum, and ammonium ions (81), sulfamic acid, and ammonium sulfate (82) have been reported as catalysts for cellulose acetate production. In general, they require reaction temperatures above 50°C for complete esterification. Relatively small amounts (<0.5%) of sulfuric acid combined with phosphoric acid (83), sulfonic acids, eg, methanesulfonic, or alkyl phosphites (84) have been reported as good acetylation catalysts, especially at reaction temperatures above 90°C. 

Stabilization and Digestion. Following the initial washing steps, the stabilization of CN occurs. This involves removal of any remaining sulfuric acid since it would catalyze the decomposition of CN. The sulfuric acid present is both physically entrained in the product and chemically bonded to the cellulose chain. CN can contain 0.2—3% esterified H2SO4, depending on the DS of nitration. The sulfonate ester can be easily removed by... 

Typically RO systems are preceded by pretreatment units to remove suspended solids/colloidal matter and add chemicals that control biological growth and reduce scaling. Membranes are typically made of synthetic polymers coated on a backing (skin). Examples of membrane materials include polyamides, cellulose acetate and sulfonated polysulfone. 

The GBR resin works well for nonionic and certain ionic polymers such as various native and derivatized starches, including sodium carboxymethylcel-lulose, methylcellulose, dextrans, carrageenans, hydroxypropyl methylcellu-lose, cellulose sulfate, and pullulans. GBR columns can be used in virtually any solvent or mixture of solvents from hexane to 1 M NaOH as long as they are miscible. Using sulfonated PDVB gels, mixtures of methanol and 0.1 M Na acetate will run many polar ionic-type polymers such as poly-2-acrylamido-2-methyl-l-propanesulfonic acid, polystyrene sulfonic acids, and poly aniline/ polystyrene sulfonic acid. Sulfonated columns can also be used with water glacial acetic acid mixtures, typically 90/10 (v/v). Polyacrylic acids run well on sulfonated gels in 0.2 M NaAc, pH 7.75. 

A powdered soap-based laundry detergent contains 44% tallow soap, 18% sodium salt of a-sulfonated 1 1 methyl stearate-methyl palmitate mixture, 9% sodium silicate, 10% Na2S04, 2.5% ethoxylated cocoethanolamide, 1.4 cellulose, 0.2% fluorescent whitener, 0.7% enzyme, 0.5% perfume, and 5% water [77]. 

As shown, an asymmetric carboxylic-sulfonic acid anhydride is formed, but the cellulose attack occurs on the C = O group, since a nucleophilic attack on sulfur is slow, and the tosylate moiety is a much better leaving group than the carboxylate group [193]. Similar to other acylation reactions, there is a large preference for tosylation at the 5 position, and cellulose tosylates... 

Synthetic examples include the poly(meth)acrylates used as flocculating agents for water purification. Biological examples are the proteins, nucleic acids, and pectins. Chemically modified biopolymers of this class are carboxymethyl cellulose and the lignin sulfonates. Polyelectrolytes with cationic and anionic substituents in the same macromolecule are called polyampholytes. 

Carboxymethylcellulose, polyethylene glycol Combination of a cellulose ether with clay Amide-modified carboxyl-containing polysaccharide Sodium aluminate and magnesium oxide Thermally stable hydroxyethylcellulose 30% ammonium or sodium thiosulfate and 20% hydroxyethylcellulose (HEC) Acrylic acid copolymer and oxyalkylene with hydrophobic group Copolymers acrylamide-acrylate and vinyl sulfonate-vinylamide Cationic polygalactomannans and anionic xanthan gum Copolymer from vinyl urethanes and acrylic acid or alkyl acrylates 2-Nitroalkyl ether-modified starch Polymer of glucuronic acid... 

Capryloamphoglycinate, cocoamphodiacetate, disodium cocoamphodiacetate, lauroamphoacetate, sodium capryloamphohydroxypropyl sulfonate, sodium mixed Cg amphocarboxylate, and alkylamphohydroxypropyl sulfonate Polyvinylpyrrolidone, polyvinyl alcohol, starches, cellulosic material, or partially hydrolyzed polyacrylamide, and polypropylene glycol, or a betaine [43]... 

A composition containing polyanionic cellulose and a synthetic polymer of sulfonate has been tested for reducing the fluid loss and for the thermal stabilization of a water-based drilling fluid for extended periods at deep well drilling temperatures [812]. 

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