Cetylpyridinium salicylate

Entangled solutions of wormy micelles, like solutions of ordinary polymers, show pronounced viscoelastic effects. Figure 12-9 shows the storage and loss moduli for a solution of 15 mM cetylpyridinium salicylate (CPySal) with 11 mM added sodium salicylate. For this solution, the storage modulus is found to be comparable to the loss modulus over a... 

Fig. 3 Shear viscosity as a function of time for equimolar cetylpyridinium salicylate (CP/Sal) at 0.9 mM (c = 0.04 wt. %) and temperature T = 20°C. The transient response at 7 = 0.1 s exhibits a regular steady behavior for such dilute solution, whereas the response at 50 s shows a period of induction during which the viscosity increases and then stabilizes around ten times the viscosity of water. Figure reprinted with permission from [51]...

W-band EPR was also recently used to help obtain accurate values for the rigid-limit g matrix and nitrogen hyperfine tensor for a spin probe (abbreviated HTAB) in a multi-frequency study of the adsorption and aggregation of the surfactants cetylpyridinium chloride and and cetylpyridinium salicylate on silica surfaces.Polarities and local viscosities (determined from the dynamics of the spin probe) were then deduced. 

Active agents vary according to use. For controlling bad breath, 2iac salts, sodium lauryl sulfate, and flavors are used. To destroy oral microorganisms, chlorhexidine, cetylpyridinium chloride [123-03-5] and ben2alkonium chloride [68391-01-5] are valuable. Essential oils, such as thymol [89-83-8] eucalyptol [470-82-6] menthol, and methyl salicylate [119-36-8] reduce plaque-related gingivitis (see Oils, essential). Sodium fluoride aids ia caries coatrol. 

A significant contribution of rheo-NMR has been to show that the uniform shear-rate assumption may be violated in the case of certain classes of fluids in which pathological flow properties are exhibited. Figure 2.8.10 shows shear-rate maps [26] obtained for the wormlike surfactant system, cetylpyridinium chloride-sodium salicylate in water. While the velocity gradients show no deviation from uniformity at very low shear rates, above a certain critical value yc a dramatic variation in the rate-of-strain across the 7° cone gap is found. In particular a very high shear-rate band is found to exist at the mid-gap. 

A PRP -1 (Hamilton Reno, NV) reversed phase column was coated with cetylpyridinium and eluted with tetramethylammonium salicylate acetoni-trile water.89 The separation was comparable to that observed on conventional ion exchange. Coated phases were also used to separate oxalate complexes of manganese, cobalt, copper, and zinc.90 Reversed phase silica supports were coated with poly(N-ethyl-4-vinylpyridinium bromide), poly(dimethydiallylammonium chloride), poly(hexamethyleneguanidinium... 

Figure 4 Images (a) and shear rate profiles (h) from a cetylpyridinium chloride sodium salicylate solution of wormlike micelles at different imposed average shear rates in the cone-and-plate geometry. The dark and bright hands show regions of fast moving approaching and receding regions of fluid (from ref 57)...

Szasz, G. Budvdri-Bdrany, Z. Lore, A. Radeczky, G. Shalaby, A. HPLC of antiphlogistic acids on silica d3TiamicaIly modified with cetylpyridinium chloride. J.Liq.Chromatogr, 1993, 16, 2335-2345 [also diclofenac, fenoprofen, ketoprofen, naproxen, nicotinic acid, nifiuminic acid, salicylic acid]... 

Ammonium alum Balsam Peru (Myroxylon pereirae) Sodium percarbonate antiseptic, mild pharmaceuticals Sodium salicylate antiseptic, mild sunscreen lotions Sodium salicylate antiseptic, mucosa Sodium iodate antiseptic, oral care Tea tree (Melaleuca altemifolia) oil antiseptic, oral pharmaceuticals Terpene resin antiseptic, oral rinses Eucalyptol Salicylic acid antiseptic, pharmaceutical ointments Tea tree (Melaleuca altemifolia) oil antiseptic, pharmaceutical topicals Didecyidimonium chloride antiseptic, pharmaceuticals Benzoic acid Bismuth subgallate Cetalkonium chloride Cetylpyridinium chloride Ethyl ether Eugenol Gum benzoin Peracetic acid Thymol 3,4,4 -Trichlorocarbanilide Urea... 

Spin probes at the fast motional limit have also been utilized in studies of heterogeneous molecular assembly by HF EPR. Cramer et al. utilized the spin probe TEMPO (2,2,6,6-tetramethylpiperedine-l-oxyl) to investigate poly(butylacrylate) and poly(butylmethacrylate) films. The same spin probe was also used by Smirnov and co-workers to study rotational diffusion of the nitroxide in two phases of aqueous phospholipid dispersions with W-band EPR. Bakker and co-workers utilized another probe - 4-[N,N-dimethyl-lV-(n-hexadecyl)ammonium]-2,2,6,6-tetramethylpiperidinyl-iV-oxyl (HTAB ) to study absorption and aggregation of cetylpyridinium chloride and cetylpyridin-ium salicylate (CPSa) on silica nanoparticles. From W-band line width analysis it was concluded that CPSa on silica surfaces forms two coexisting aggregate phases, one which excludes HTAB and one in which HTAB is concentrated. 

There is now very strong evidence for a micellar phase in several aqueous cationic surfactant systems in the presence of added salt, such as cetyltri-methylanunonium bromide or chloride (CTAB or CTAC) with added KBr or sodium salicylate (NaSal), cetylpyridinium bromide (CPyBr) + KBr, ce-... 

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