Surfactants sodium lauryl sulfate

Another, more recent example by Rodriguez-Hornedo and co-workers elegantly displayed how micellar additives, such as surfactants, can bring thermodynamic stability to unstable co-crystal phases. An incongruently dissolving carbamazepine salicyclic acid co-crystal was tested and it was found that by introducing various concentrations of aqueous solutions of sodium lauryl sulfate (surfactant), a congruently saturated system resulted. 

SLS (sodium lauryl sulfate surfactant) CH2=9H Hexadecane (costabilizer)... 

The kinetics of vinyl acetate emulsion polymeriza tion in the presence of alkyl phenyl ethoxylate surfactants of various chain lengths indicate that part of the emulsion polymerization occurs in the aqueous phase and part in the particles (115). A study of the emulsion polymerization of vinyl acetate in the presence of sodium lauryl sulfate reveals that a water-soluble poly(vinyl acetate)—sodium dodecyl sulfate polyelectrolyte complex forms, and that latex stabihty, polymer hydrolysis, and molecular weight are controlled by this phenomenon (116). 

The surfactant most commonly used is the anionic detergent sodium lauryl sulfate. Other surfactants that have been used include sodium dodecylbenzene sulfonate [25155-30-0] sodium A/-lauroyl sarcosinate or Gardol [137-16-6] and sodium cocomonoglyceride sulfonate [3694-90-4]. Cationic and nonionic surfactants are not used for several reasons, including incompatibiUty with the abrasive system and lack of high foaming capabiUty. 

Removal of general organic fouling is best achieved by alkaline cleaning based on caustic, EDTA, and a surfactant such as sodium dodecyl sulfate or sodium lauryl sulfate. 

Sodium chloride (table salt) is used to thicken the mixture if the main surfactants are sodium lauryl sulfates. If the surfactants are ammonium-based, then ammonium chloride is used instead. Salt can make the shampoo harsh, which can sting the eyes, so more expensive thickeners are used to keep the salt levels low. 

Fluorides work better in combination with surfactants, which help the remineralization process. The most common are the lauryl sulfates, such as sodium lauryl sulfate or ammonium lauryl sulfate. 

Alcohol sulfates commonly have free alcohol and electrolytes as impurities. Other hydrophobic impurities can also be present. A method suitable for the purification of surfactants has been proposed by Rosen [120]. Consequently, commercial products have CMCs that deviate from the accepted reference values. This was demonstrated by Vijayendran [121] who studied several commercial sodium lauryl sulfates of high purity. The CMC was determined both by the conductimetric method and by the surface tension method. The values found were similar for both methods but while three samples gave CMC values of 7.9, 7.8, and 7.4 mM, close to the standard range of 8.0-8.2 mM, three other samples gave values of 4.1, 3.1, and 1.7 mM. The sample with a CMC of 7.9 mM was found to have a CMC of 8.0 mM with no detectable surface tension minima after purification and recrystallization. This procedure failed in all other cases. 

The ocular irritation caused by cosmetic ingredients has been evaluated by the determination of the amount of histamine contained in tears. Contact of surfactants and the eye tissue cause an immediate dose-dependent release of histamine through direct cytotoxic damage of cell membranes. This method has been tested with sodium lauryl sulfate with volunteers [187]. 

Before use, condition the new electrode by employing it in the titration of a sodium lauryl sulfate solution with a solution of Hyamine 1622 or benzetho-nium chloride solution, 0.04 M using a silver-silver chloride reference electrode. During this conditioning, a layer of an insoluble cation-anion complex becomes firmly attached to the plasticized PVC coating rendering it sensitive to both anionic and cationic surfactants. 

DLSS, DPMS, DSIS, and a blend containing SLAS and DCAD are the components to improve the formulations skin mildness, i.e., the skin compatibility of the other surfactants present. SLES/ALAS/SLAS, i.e., sodium lauryl ether sulfate, ammonium lauryl sulfate, sodium lauryl sulfate, are examples of high-foaming basic surfactants. 

Sodium lauryl sulfate and/or DLAS DCOS DLMS DRMS Sodium lauryl isethionate Sulfoacetate Other surfactants... 

While in the past mainly sodium lauryl sulfate was the surfactant of choice, recently more skin-compatible materials have taken its place. 

Skin feels dull when sodium lauryl sulfate is the main surfactant. A sulfo-succinate as the main surfactant imparts a smooth feeling to the skin. 

Water serves as a base value in this test and sodium lauryl sulfate as a well-known irritating surfactant. Lauryl ether sulfate served as a substance with high sales volume and good skin tolerance. As was to be expected, lauryl ether sulfate scored only slightly better than lauryl sulfate. Sulfosuccinate values obtained were classified under little skin roughening effect. ... 

C12-0077. Of the following compounds, which will be the best and which will be the worst surfactant Support your choices with molecular pictures, (a) propanoic acid, H3 CCH2 CO2 H (b) sodium lauryl sulfate, H3 C (CH2)n OSO3 Na and (c) lauryl alcohol,... 

Ong et al. [134] found that several hydrophilic anionic, non ionic, or cationic surfactants can alleviate the deleterious effect of magnesium stearate over-mixing on dissolution from capsules when added with the lubricant in a ratio as low as 1 5 (w/w). These successful surfactants were sodium A-lauroyl sarcosinate, sodium stearoyl-2-lactylate, sodium stearate, polox-amer 188, cetylpyridinium chloride, and sodium lauryl sulfate. The lipophilic surfactant glyceryl monostearate did not alleviate the magnesium stearate mixing effect. A reduction in thier particle size was shown to enhance effectiveness, particularly in the case of surfactants with low solubility and slow dissolution rate. 

JR Crison, ND Weiner, GL Amidon. Dissolution media for in vitro testing of water-insoluble drugs Effect of surfactant purity on in vitro dissolution of carbama-zepine in aqueous solutions of sodium lauryl sulfate. J Pharm Sci 86 384-388, 1997. 

Figure 7.9.1 The molecular structure of the anionic surfactant sodium lauryl sulfate.

Fig. 16 Effect of paracetamol granule size on tablet hardness. Curve 1 paracetamol granules with no added surfactant curve 2 paracetamol granules with 0.2% w/v sodium lauryl sulfate. (From Ref. 81.)...

Howard [27] determined dissolved aluminium in seawater by the micelle-enhanced fluorescence of its lumogallion complex. Several surfactants (to enhance fluorescence and minimise interferences), used for the determination of aluminium at very low concentrations (below 0.5 pg/1) in seawaters, were compared. The surfactants tested in preliminary studies were anionic (sodium lauryl sulfate), non-ionic (Triton X-100, Nonidet P42, NOPCO, and Tergital XD), and cationic (cetyltrimethylammonium bromide). Based on the degree of fluorescence enhancement and ease of use, Triton X-100 was selected for further study. Sample solutions (25 ml) in polyethylene bottles were mixed with acetate buffer (pH 4.7, 2 ml) lumogallion solution (0.02%, 0.3 ml) and 1,10-phenanthroline (1.0 ml to mask interferences from iron). Samples were heated to 80 °C for 1.5 h, cooled, and shaken with neat surfactant (0.15 ml) before fluorescence measurements were made. This procedure had a detection limit at the 0.02 pg/1 level. The method was independent of salinity and could therefore be used for both freshwater and seawater samples. 

Ross and Miles foam heights with amide fatty acid amides, 2 456t viscosity enhancement, 2 455t Sodium lauryl sulfate, 24 145 cosmetic surfactant, 7 834t effect of coconut diethanolamide on foaming, 2 453t... 

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