Potassium persulfate, and

Methylene iodide [75-11-6], CH2I2, also known as diio dome thane, mol wt 267.87, 94.76% I, mp 6.0°C, and bp 181°C, is a very heavy colorless Hquid. It has a density of 3.325 g/mL at 20°C and a refractive index of 1.7538 at 4°C. It darkens in contact with air, moisture, and light. Its solubiHty in water is 1.42 g/100 g H2O at 20°C it is soluble in alcohol, chloroform, ben2ene, and ether. Methylene iodide is prepared by reaction of sodium arsenite and iodoform with sodium hydroxide reaction of iodine, sodium ethoxide, and hydroiodic acid on iodoform the oxidation of iodoacetic acid with potassium persulfate and by reaction of potassium iodide and methylene chloride (124,125). Diiodoform is used for determining the density and refractive index of minerals. It is also used as a starting material in the manufacture of x-ray contrast media and other synthetic pharmaceuticals (qv). 

The most common water-soluble initiators are ammonium persulfate, potassium persulfate, and hydrogen peroxide. These can be made to decompose by high temperature or through redox reactions. The latter method offers versatility in choosing the temperature of polymerization with —50 to 70°C possible. A typical redox system combines a persulfate with ferrous ion ... 

The polymerization reaction is conducted at the desired temperature with a slow stirring regime for a certain period. A typical recipe for the emulsion polymerization of styrene is exemplified in Table 1 [40]. As seen here, potassium persulfate and sodium dodecyl sulfate were used as the initiator and the stabilizer, respectively. This recipe provides uniform polystyrene particles 0.22 /Lim in size. 

Rasmussen and co-workers. Chapter 10, have shown that many free-radical polymerizations can be conducted in two-phase systems using potassium persulfate and either crown ethers or quaternary ammonium salts as initiators. When transferred to the organic phase persulfate performs far more efficiently as an initiator than conventional materials such as azobisisobutyronitrile or benzoyl peroxide. In vinyl polymerizations using PTC-persulfate initiation one can exercise precise control over reaction rates, even at low temperatures. Mechanistic aspects of these complicated systems have been worked out for this highly useful and economical method of initiation of free-radical polymerizations. 

A critical survey of the literature on free radical polymerizations in the presence of phase transfer agents indicates that the majority of these reactions are initiated by transfer of an active species (monomer or initiator) from one phase to another, although the exact details of this phase transfer may be influenced by the nature of the phase transfer catalyst and reaction medium. Initial kinetic studies of the solution polymerization of methyl methacrylate utilizing solid potassium persulfate and Aliquat 336 yield the experimental rate law ... 

In 1981 we reported (2, 3) the first examples of free radical polymerizations under phase transfer conditions. Utilizing potassium persulfate and a phase transfer catalyst (e.g. a crown ether or quaternary ammonium salt), we found the solution polymerization of acrylic monomers to be much more facile than when common organic-soluble initiators were used. Somewhat earlier, Voronkov and coworkers had reported (4) that the 1 2 potassium persulfate/18-crown-6 complex could be used to polymerize styrene and methyl methacrylate in methanol. These relatively inefficient polymerizations were apparently conducted under homogeneous conditions, although exact details were somewhat unclear. We subsequently described (5) the... 

Our kinetic studies have concentrated on the polymerization of MMA in organic solution using solid potassium persulfate and a phase transfer catalyst. 

In aqneous tert-butanol, pulse radiolysis of potassium persulfate and p-nitrobenzaldehyde induced consecutive reactions with the eventual formation of the p-formylphenoxyl radical (Geeta et al. 

Since relatively stable macroradicals are produced in the emulsion process, the termination rate decreases and a high molecular weight product is rapidly produced. It is customary to use a water-soluble initiator such as potassium persulfate and an anionic surfactant... 

Polymer-supported persulfonic acid was prepared from potassium persulfate and the cation exchange resin P—SO3H in water. The authors reported various applications of this new oxidizing reagent such as epoxidation of olefins, Baeyer-Villiger reaction and cleavage of disulfide and Af-formylamino acids. 

The most common initiators are acyl peroxides, hydroperoxides, or azo compounds. Hydrogen peroxide, potassium persulfate, and sodium perborate are popular in aqueous systems. Ferrous ion in some cases enhances the catalytic effectiveness. 

Add 128.2 g of distilled water, 71.2 g of styrene, 31.4 ml of 0.680% potassium persulfate, and 100 ml of 3.56% soap solution (see Note 1) to a three-neck round bottom flask equipped with a mechanical stirrer, condenser, and nitrogen inlet tube. 

On the other hand, chemicals might be chosen as agents for generation of active centers in the polymeric backbone and grafting of monomer in the vapor phase. Ammonium persulfate and styrene (189), acrylic acid (190), butyl acrylate (191), potassium persulfate and n-butyl maleate or 2-ethyl hexyl acrylate (55,134) and ammonium ceric nitrate and methacrylic add (192) are examples of this method. Benzoyl peroxide deposited on polycaprolactam fibers initiates the grafting of styrene in vapor phase (193). 

Cobalt- or manganese-substituted PW12O40 and SiWiiOj9Ru(OH2)5 catalyze the oxidation of paraffins such as cyclohexane and adamantane (320, 321) as well as the epoxidation of cyclohexene with ter/-butyl hydroperoxide, iodosylbenzene potassium persulfate, and sodium periodate (321, 322). The reactivity depends on the transition metals. In the case of epoxidation of cyclohexene with iodosylbenzene, the order of catalytic activity of PW] i(M)03 is M = Co > Mn > Cu > Fe, Cr. 

Earlier work on the determination of total mercury in river sediments also include that of Iskander et al. [27]. Iskander applied flameless atomic absorption to a sulfuric acid-nitric acid digest of the sample following reduction with potassium permanganate, potassium persulfate and stannous chloride. A detection limit of one part in 109 is claimed for this somewhat laborious method. 

The material balance of the strong-acid groups showed a theoretical total of 0.194 meq/gm polymer from the sodium lauryl ether sulfate, potassium persulfate, and sodium hydrosulfite, in comparison with a measured total of 0.205 meq/gm (0.026 on particle surface 0.179 in serum) by serum replacement and a total of 0.215 meq/gm by ion exchange with Dowex 50W(H+). The material balance of the acrylic acid showed that 29.9% was on the particle surface, 28.6% in the aqueous serum, and 41.5% buried inside the particle. The sodium lauryl ether sulfate found in the serum amounted to 78% of that added by Hyamine 1622 titration and 88% by thin-film chromatography. The nonylphenol polyoxyethylene adduct amounted to 113% by iodine-iodide titration and 91% by thin-film chromatography. ... 

Styrene (99% pure) was obtained from Fisher Scientific and Aldrich Chemicd. It was used either as supplied or after purification to remove the inhibitor. To remove the inhibitor, styrene (Aldrich) was washed three time with 10% sodium hydroxide and dried over phosphorus pentoxide in a desiccator after repeated washing with water. The purified sample was stored under nitrogen at 0<>C. Potassium persulfate and AIBN initiators were obtained from Fisher and DuPont, respectively, and were used without further purification. Sodium... 

Esters have been prepared in 63-73% yields from several simple cycloalkyl and aryl alkyl ketones by reaction at room temperature with per-benzoic acid. The larger radical of the ketone appears as the alcohol fragment of the ester. Cyclic ketones are oxidized by potassium persulfate and sulfuric acid to esters from which o>-hydroxy aliphatic esters are obtained upon hydrolysis and reesterification. Peracetic acid in acetic anhydride converts salicylaldehyde to o-hydroxyphenyl formate (88%). ... 

Persulfate-bisulfite-initiated graft polymerization was accomplished (Table I) using the procedure of Feairheller et al (11). Lyophilized rat skins were soaked in 100 ml of a 0.4% aqueous solution of an octyl-phenyl ether of polyethylene glycol containing 9-10 ethylene oxide groups. After 1 hr, 0.4 g potassium persulfate and 0.135 g sodium bisulfite were added, and CO2 was passed through the solution before 5 ml of monomer were added. 

Orders of Reaction for the Rates with Potassium Persulfate and Rediation Polymerization of Vinyl Acetate ... 

Oxidants suitable for the partial oxidation of amines to nitroso compounds are peroxy acids Caro acid, which is prepared in situ from potassium persulfate and sulfuric acid [195, 199 potassium peroxysulfate (Oxone) [295] peroxyacetic acid [i53], and peroxybenzoic add [1186], 3-Nitro-o-toluidine [195] and 5-nitro-o-toluidine [199] in aqueous-alcoholic solutions, when treated with a mixture of potassium persulfate and concentrated sulfuric acid, give 3-nitro-2-nitrosotoluene and 5-nitro-2-nitrosotoluene in respective yields of 60 and 55-66%. Organic peroxy acids convert 2,6-dihaloanilines into 2,6-dihalonitrosobenzenes (equation 497) [753, 1186]. p-Phenylenediamine (1,4-diaminobenzene) is oxidized by Oxone (2KHS05 KHS04 K2S04) in an aqueous suspension at room temperature to p-dinitrosobenzene in a quantitative yield [205]. 

Free radical catalysts, such as potassium persulfate and azo compounds, are ineffective in initiating this type of polymerization of isocyanates. Also, catalysts, such as triethylphosphine and triethylamine, which are known to catalyze dimer and triraer formation at higher temperatures, are not effective in initiating the polymerization to linear 1-nylons. 

Potassium persulfate and Ammonium persuifate, K2S20g, (NH4)2S20n. Mol. wts. 270.33,228.21.5ee also Caro s acid. 

The behavior of A -3-ketosteroids on oxidative cleavage - is illustrated by the reaction of testosterone propionate (1). Pettit and Kasturi mixed 9 g. of potassium persulfate and 10 g. of coned, sulfuric acid in a mortar, diluted with 150 ml. of acetic acid, added the mixture to a solution of 9 g. of testosterone propionate in 150 ml. of acetic acid, and let the mixture stand with intermittent shaking at room temperature for 7 days. Workup included saponification and reacidifleation, and the product (2 g.) was characterized as the lactone 3-oxo-17/3-hydroxy-4-oxa-5a-androstane (4). A possible reaction sequence is formulated. 

Another efficient conversion of alcohols to aldehydes was achieved using potassium persulfate and 3-methyUmidazolium methanesulfonate by Chaskar and his coworkers (Scheme 14.55) [61]. 

Sodium-p-styrene sulfonate (SST) was supplied by Exxon Research and Engineering Co. and used without further purification. n-Butyl acrylate was a product of Polysciences, Inc. and was passed through a column of neutral alumina, twice, before use to remove the inhibitor. Potassium persulfate and sodium bisulfate were recrystallized from distilled water and dried under vacuum. 

Inverse Emulsion Polymerization. Water-soluble monomers can be polymerized by emulsifying water solutions of these monomers in an organic continuous phase. This process, called inverse emulsion polymerization, yields a product comprised of a colloidal suspension of droplets of aqueous polymer solution. The original study of an inverse system by Vanderhoff et al. (20) involved the monomer sodium p-vinyIbenzene sulfonate, an organic phase of xylene. Span 60 as the emulsifier, and either benzoyl peroxide or potassium persulfate initiator. Later work by Kurenkov et al. (21) involved acrylamide in a toluene continuous phase, potassium persulfate, and Sentaraid-5 (emulsifier). DiStefano (22) examined three monomers acrylamide, dimethylaminoethyacrylate... 

The reaction is efficiently catalyzed by water-soluble peroxidic compounds, of which hydrogen peroxide, urea peroxide, potassium persulfate, and sodium perborate are widely employed. Cumene hydroperoxide also has proved to be a most interesting and useful catalyst, particularly in the production of synthetic rubber GR-S, because of its particular solubility characteristics in both the aqueous and the hydrocarbon phase. 

The free-radical copolymerization of acrylamide with three common cationic comonomers diallyldimethylammonium chloride, dimethyl-aminoethyl methacrylate, and dimethylaminoethyl acrylate, has been investigated. Polymerizations were carried out in solution and inverse microsuspension with azocyanovaleric acid, potassium persulfate, and azobisisobutyronitrile over the temperature range 45 to 60 C. The copolymer reactivity ratios were determined with the error-in-variables method by using residual monomer concentrations measured by high-performance liquid chromatography. This combination of estimation procedure and analytical technique has been found to be superior to any methods previously used for the estimation of reactivity ratios for cationic acrylamide copolymers. A preliminary kinetic investigation of inverse microsuspension copolymerization at high monomer concentrations is also discussed. 

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