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Preparation ammonium persulfate

The gel was prepared by mixing 66 ml of gel buffer (0.01 M Cd(C104)2, 0.01 M sodium polyphosphate, pH 11) 7.4 ml acrylamide solution (44.4 g of acrylamide, 1.2 g of methylene-bisacrylamide in 100 ml water) and 62.4 ml water in round bottom flask and deaerated for 5 min with a water pump. Then 1.2 ml of freshly prepared ammonium persulfate solution (150 mg in 10 ml water) and 0.1 ml of N,N,N, N tetramethylethylenediamine (TEMED) were added and mixed carefully to avoid the introduction of air. Finally, 100 ml of the resulting solution was poured carefully, to minimize the introduction of air, into a 25 mm-diameter tube. The monomer solution was overlayered with water to remove the meniscus and reduce the entry of air. The polymerization was allowed to proceed overnight at room temperature. The resulting gel, having a polymer concentration of 2.5% and a cross-link density of 2.6%, was used in a home made apparatus. ... [Pg.122]

Copolymers of diallyl dimethyl ammonium chloride [7398-69-8] with acrylamide have been used in electroconductive coatings (155). Copolymers with acrylamide made in activated aqueous persulfate solution have flocculating activity increasing with molecular weight (156). DADM ammonium chloride can be grafted with cellulose from concentrated aqueous solution catalysis is by ammonium persulfate (157). Diallyl didodecylammonium bromide [96499-24-0] has been used for preparation of polymerized vesicles (158). [Pg.88]

The most commonly used combination of chemicals to produce a polyacrylamide gel is acrylamide, bis acrylamide, buffer, ammonium persulfate, and tetramethylenediarnine (TEMED). TEMED and ammonium persulfate are catalysts to the polymerization reaction. The TEMED causes the persulfate to produce free radicals, causing polymerization. Because this is a free-radical driven reaction, the mixture of reagents must be degassed before it is used. The mixture polymerizes quickly after TEMED addition, so it should be poured into the gel-casting apparatus as quickly as possible. Once the gel is poured into a prepared form, a comb can be appHed to the top portion of the gel before polymerization occurs. This comb sets small indentations permanently into the top portion of the gel which can be used to load samples. If the comb is used, samples are then typically mixed with a heavier solution, such as glycerol, before the sample is appHed to the gel, to prevent the sample from dispersing into the reservoir buffer. [Pg.182]

An alternative method of preparing the saturated cyclic amines via cyclopolymerization of diallylamine or diallylammonium chloride was unsuccessful. Common free radical initiators such as 2,2 -azobisisobutyronitrile, ammonium persulfate, benzoyl peroxide were found to be ineffective. Several procedures reported in the literature were followed, and unfortunately all of them have resulted only a small amount of low molecular weight oligomers. Further research for polymerization conditions and types of initiation is still required. [Pg.134]

Polymers Polyacrylamide and hydrolyzed polyacrylamide were prepared by the American Cyanamid Company specifically for this project, starting with l C labelled monomer. The radioactivity level of the monomer was kept below 0.20 mC /g in order to avoid significant spontaneous polymerization, utilizing a copper inhibitor. The homopolymer was synthesized by free radical solution polymerization in water at 40°C, using monomer recrystallized from chloroform, an ammonium persulfate-sodium metabisulfite catalyst system, and isopropanol as a chain transfer agent. Sodium... [Pg.394]

Grafting and networking may modify the mechanical, chemical, and functional properties of polymers and enhance their utilization for some purposes, such as for water treatment (Kumar and Verma, 2007 Mishra et al., 2003). Psyllium derivatives were prepared by grafting acrylonitrile onto psyllium molecules using a ceric ammonium nitrate and nitric acid system (Mishra et al., 2003). The resulted grafted psyllium samples were not soluble in commonly used solvents or their combinations. In 2007, methacrylic acid derivatives of psyllium were prepared using ammonium persulfate as initiator and cross-linked using N,N-methylenebisacryla-mide as the crosslinker (Kumar and Verma, 2007). The modified psyllium... [Pg.214]

The synthesis of polyaniline and copolymers of aniline with o-nitroaniline is aimed at obtaining an electroactive material. This material can be used, for example, as an electrode in conjunction with the magnesium electrode to construct chemical power sources. The polymers were prepared by oxidation of aniline or its mixture with nitroaniline ammonium persulfate in aqueous hydrochloric... [Pg.359]

Polymerizations Where possible, polymers and copolymers were prepared in normal saline buffered with 10 mM sodium phosphate (PBS), pH 7.4, by room temperature initiation of 1% monomer solutions using 40 mM TEMED (HCl) and 5 mM ammonium persulfate. However, due to poor solubility, 0.2% solutions of NTBAAM and proporationately lower initiator concentrations were used. [Pg.256]

Prepare the initiator feed by dissolving 0.4 g of ammonium persulfate in 40 ml of deionized water. [Pg.4]

The procedure for using aqueous Caro s acid as an oxidizing agent usually involves the preparation of the dilute acid from either potassium persulfate or ammonium persulfate. The following preparation illustrates the method [80],... [Pg.460]

Premixed blends of acrylamide and bisacrylamide prepared with varius ratios of monomers were purchased from Eastman Kodak Chemical Company (Rochester, NY). The 37.5 1 and the 19 1 preparations were used for the study. Gels made from these mixtures will be referred to as 2.6% and 5% cross-linked polyacrylamides, respectively. Five grams of each monomer blend were added to 95-g portions of distilled water. Solution was achieved by mixing for 1 h. To each sample was added 1 ml each of a 1% solution of N, N, N, N -tetramethylethylenediamine (Eastman Chemical Co., New Haven, CT) and a 10% solution of ammonium persulfate (Mallinckrodt Laboratory Chemicals, Phillipsburg, N.1). The solutions were poured into an open polyethylene mold and allowed to cure for 12 h at room temperature. The gels were carefully removed and placed in an excess of distilled sterile water for 48 h. The water was replaced several times during the equilibration period. It was felt that this was sufficient to remove unreacted monomers and impurities. The gels were then cut with a steel-ruled die into circles 40 imn in diameter. [Pg.179]

Oxidized Starches. Alkaline hypochlorite treatment introduces carboxyl and carbonyl groups, effects some depolymerization, and produces whiter (bleached) products that produce softer, clearer gels. Ammonium persulfate is used in some paper mills with continuous thermal cookers to prepare in situ bigb solids, low viscosity dispersions. Most of the hypochlorite-oxidized starch and all the ammonium persulfate-oxidized starch is used in the paper industry. The low solution viscosity and good binding and adhesive properties of these products make them especially effective in high solids, pigmented... [Pg.485]

The reaction of [NiL] (H2L = 76a) with ammonium persulfate, pyruvic acid and AgN03 gives (76b) which acts as an N202 donor to a number of transition metals. The complexes [ZnL] (H2L = 76a or 76b) have been prepared, and their electronic spectra reported.533... [Pg.955]

Ammonium persulfate solution, 1.0 g/ 10 mL of phosphate buffer (prepare fresh just before use)... [Pg.393]

The sample used to study the relationship between the volume phase transition and the frictional property is poly( /V-isopropylacrylamide) gel which shows a small discontinuous volume phase transition at 33.6 °C. The sample gel is prepared by free radical polymerization 7.8 g of re-crystallized N-iso-propylacrylamide (main constituent, Kodak), 0.133 g lV,iV -methylenebis-acrylamide (cross-linker, Bio-Rad), 240 ml tetramethylenediamine (accelerator, Bio-Rad), and 40 mg ammonium persulfate (initiator, Mallinckrodt) are dissolved in distilled water (100 ml) at 0°C. The gel mold is immersed in the pre-gel solution and then degassed for 40 min at 0°C. The temperature is raised to 20.0 °C after this treatment to initiate the gelation reaction. The sample gel thus obtained is homogeneous and transparent, at least by visual inspection. [Pg.42]

Gels were prepared by a free radical copolymerization in water at 0 °C. A capillary of inner diameter of 141.5 pm (1.35 mm only for the samples described in the next section) was used to make a uniform cylindrical shape. The reagents and their amounts were standard [8] purified NIPA (Kodak), 690 mM as the main polymer constituent, JV,lV,lV, lV -tetramethylethylenediamine (Bio-Rad or Wako), 240 pi/100 ml water as accelerator and ammonium persulfate (Mallin-crodt or Wako), 40 mg/100 ml water as initiator. The cylindrical gels were taken out and kept in water for several days, hereafter, the gels were placed in water solutions of various salt concentrations. The diameter was measured after the gels reached equilibrium at each temperature. Temperature was controlled with an accuracy of 0.05°C. [Pg.227]

Prepare stacking gel solution according to Table B3.1.3 in a side-arm vacuum flask, leaving out the ammonium persulfate and TEMED. [Pg.160]

Polyacrylamide is a cross-linked polymer of acrylamide. These gels are more difficult to prepare than agarose. Monomeric acrylamide (which is a known neurotoxin) is polymerized in the presence of free radicals to form polyacrylamide. The free radicals are provided by ammonium persulfate and stabilized by TEMED (/V/V/V/V -tetramethylethylenediamine). The chains of polyacrylamide are cross-linked by the addition of methylene-bisacrylamide to form a gel whose porosity is determined by the length of chains and the degree of cross-linking. The chain length is proportional to the acrylamide concentration usually between 3.5 and 20%. Cross-linking bis-acrylamide is usually added at the ratio 2 g bis/38 g acrylamide. [Pg.361]


See other pages where Preparation ammonium persulfate is mentioned: [Pg.397]    [Pg.485]    [Pg.510]    [Pg.214]    [Pg.31]    [Pg.284]    [Pg.37]    [Pg.248]    [Pg.411]    [Pg.42]    [Pg.244]    [Pg.224]    [Pg.460]    [Pg.187]    [Pg.244]    [Pg.113]    [Pg.393]    [Pg.163]    [Pg.205]    [Pg.219]    [Pg.1105]    [Pg.113]    [Pg.393]    [Pg.79]    [Pg.264]    [Pg.281]    [Pg.434]    [Pg.26]    [Pg.67]   
See also in sourсe #XX -- [ Pg.393 , Pg.412 ]

See also in sourсe #XX -- [ Pg.393 , Pg.412 ]




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