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Nonionic poly surfactant

Lignites and lignosulfonates can act as o/w emulsifiers, but generally are added for other purposes. Various anionic surfactants, including alkylarylsulfonates and alkylaryl sulfates and poly(ethylene oxide) derivatives of fatty acids, esters, and others, are used. Very Httle oil is added to water-base muds in use offshore for environmental reasons. A nonionic poly(ethylene oxide) derivative of nonylphenol [9016-45-9] is used in calcium-treated muds (126). [Pg.182]

V. Schmitt, C. Cattelet, and F. Leal-Calderon Coarsening of Alkane-in-Water Emulsions Stabilized by Nonionic Poly(Oxyethylene) Surfactants The Role of Molecular Permeation and Coalescence. Langmuir 20, 46 (2004). [Pg.170]

Recently, a new class of inhibitors (nonionic polymer surfactants) was identified as promising agents for drug formulations. These compounds are two- or three-block copolymers arranged in a linear ABA or AB structure. The A block is a hydrophilic polyethylene oxide) chain. The B block can be a hydrophobic lipid (in copolymers BRIJs, MYRJs, Tritons, Tweens, and Chremophor) or a poly(propylene oxide) chain (in copolymers Pluronics [BASF Corp., N.J., USA] and CRL-1606). Pluronic block copolymers with various numbers of hydrophilic EO (,n) and hydrophobic PO (in) units are characterized by distinct hydrophilic-lipophilic balance (HLB). Due to their amphiphilic character these copolymers display surfactant properties including ability to interact with hydrophobic surfaces and biological membranes. In aqueous solutions with concentrations above the CMC, these copolymers self-assemble into micelles. [Pg.605]

The use of sc C02 instead of toluene as a solvent leads to some rate enhancement in these two systems, although it is clear that this activity is still not practical for most nonpolar, nonvolatile substrates. Significant improvements to the biphasic water/supercritical C02 system were accomplished by forming H20/C02 emulsions using newly developed surfactants (Jacobson et al., 1999). Three different surfactants were used that form water in C02 (w/c) or C02 in water (c/w) emulsions (1) anionic surfactant perfluoropolyether ammonium carboxylate, (2) cationic Lodyne 106A, and (3) nonionic poly(butylene oxide)-h-poly(ethylene oxide). The low interfacial tension, y, between water and C02 (17 mNm-1 at pressures above 70 bar), which is significantly lower than water/alkane systems (30-60 mNm-1),... [Pg.42]

Both hydrophilic and lipophilic surfactants can be used to stabilize the polymeric nanoparticles. Generally the lipophilic surfactant is a natural lecithin of relatively low phosphotidylcholine content, whereas the hydrophilic one is synthetic anionic (lauryl sulfate), cationic (quaternary ammonium), or more commonly nonionic [poly(oxyethylene)-poly(propylene)glycol]. Nanoparticles can be prepared in the absence of surfactants, but there are lots more chances to get aggregated during storage. [Pg.365]

Detailed studies were performed on the copper-catalyzed suspension or emulsion polymerizations.249 Living or controlled emulsion radical polymerization of nBMA can be achieved in the presence of nonionic poly(oxyethylene)-based surfactants such as Brij 97, Brij 98, and Tween 20 with the F21 (X = Br)/CuBr/ L-3 or L-4 system.249,251,252 The Mn increased in direct proportion to monomer conversion up to 5 x 104 (MJ Mn = 1.1 —1.2). The particle sizes are around 1000— 4000 nm, suggesting a suspension, but can be reduced to about 300 nm with the use of hexadecane as a cosurfactant along with ultrasonication.249 252... [Pg.479]

Mixed solutions of cationic surfactants and nonionic poly(ethylene glycol) or block copolymers were employed for the synthesis of monolithic trimodal porous silica.[176] Lyotropic mixtures of block copolymers of different lengths with hydrophilic linear PEO chains were also applied to their nanocasting into bimodal micro-mesoporous silica to formulate the dependence of the mesopore sizes and the microporosity on the lengths or sizes of the hydrophobic and the hydrophilic blocks, but the mesostructures were worm-type in morphology and several hundred nanometers or more in size. [Pg.533]

The potential of microemulsions for organometaUic-catalyzed hydrogenations in water/scC02 biphasic systems has been assessed using the rhodium-catalyzed hydrogenation of styrene as a common test reaction [Eq. (7)] [31]. The water-soluble Wilkinson complex [RhCl(TPPTS)3] was applied as catalyst precursor together with anionic perfluoropolyether carboxylates, cationic Lodyne A, or nonionic poly-(butene oxide)-b-poly(ethylene oxide) surfactants. The interfacial tension is small in the presence of the supercritical fluid and small amounts of surfactant (0.1-2.0 wt.%) suffice to form stable microemulsions. The droplet diameter of the microemulsions varied between 0.5 and 15 pm and a surface area of up to 10 m was obtained. [Pg.725]

In this particular field, it is noted that polymers are not used as stmctural materials, strictly speaking, but as a tool for formulation (polymer formulation as opposed to the formulation of polymers commonly used). They are found here ranging from the micrometric scale as a component of nanoparticles to the micelle, or even the macromolecule in the case of nonionic polymer surfactants for the stabilization of particles [HAM 11, TAD 01]. A self-association leads to particle sizes from 50 to 80 nm in water in the presence of poly(ethylene gfycol). Nanoparticles can also be obtained with associative polymers which spontaneously self-assemble [GRE 11]. [Pg.396]

The ability of some low-molecular-weight nonionic siloxane surfactant aqueous solutions to rapidly spread over a variety of hydrophobic surfaces, such as polyethylene and paraffin wax, has been known for a long time. It is now clearer that this intriguing and useful property is confined to the branched heptamethyltrisiloxane (Me3SiO)2MeSi hydrophobe, but not limited to the nonionic poly(oxyethylene) hydrophile for example, superwetting cationic quaternary ammonium salts have been identified. It is also evident that this is a... [Pg.682]

Self-assembly of block copolymers that are made of poly(ethylene oxide), PEO, as the hydrophilic non-ionic block, has been extensively explored. The research interest in PEO-containing block copolymers was motivated, to a great extent, by potential biomedical applications, which rely on the finding that PEO moieties are biocompatible. Because amphiphilic block copolymers of PEO and poly(propylene oxide) PPO (pluronics) are produced on an industrial scale, research on these nonionic polymeric surfactants resulted in many technological applications. Both PPO and PEO are thermoresponsive, having a low solution critical temperature (LSCT),... [Pg.59]

Chem. Descrip. PEG 600 CAS 25322-68-3 EINECS/ELINCS 229-859-1 Uses Chemical intennediate for prod, of surfactants for cleaners, textiles, paper, cosmetics, personal care prods., rubber mold releases, printing inks and dy, metalworking fluids, foods, paints, paper, wood prods., adhesives, agric., ceramics, elec, equip., petrol, prods., photographic prods., resins earner for pharmaceuticals Pre terties APHA 25 max. liq. m.w. 600 sol. in water, acetone, ethanol, ethyl acetate, toluene sp.gr. 1.127 dens. 9.4 Ib/gal vise. 10.5 cs (99 C) f.p. 20-25 C flash pt. 246 C (COC) pour pt. 19-24 C nonionic Poly-G 1000 [BASF/Perf. Chems.)... [Pg.648]

Antonietti et al. described the preparation of mesoporous silica in systems containing mixtures of nonionic fluorinated surfactants and nonionic hydrocarbon block copolymer surfactants [60], The fluorinated surfactant was CF3(CF2)6-i6 C2H4(E0)4 5 and the hydrocarbon-based copolymer was poly(ethylene-co-bulylene)-block-poly(ethylene oxide). [Pg.226]

In Figure 20.17, we compare a polymer-surfactant mixture, a nonionic polyoxyethylene surfactant and dextran, with a related polymer-polymer mixture, poly(ethylene glycol) and dextran. We can see that the two mixtures phase-separate in qualitatively the same way. [Pg.453]

It was also shown that the core materials influence the conductivity of the composite particles. Nano-sized PS-PPy composites have been reported by Xu et aL [72], who also noted that when the cationic, nonpolymerizable surfactant cetyl-triemethylammonium bromide (CTAB) was used as stabilizer, the latex particles prepared showed poor colloidal stability and low electrical conductivity (Fig. 6.13) compared to that of latexes stabiHzed by nonionic polymerizable surfactant (o-methoxy[poly(ethylene oxide)4Q] undecyl a-methacrylate (PEO-R-MA-40) and cationic polymerizable surfactant (o-acryloyloxyundecyltrimethylammonium bromide (AUTMAB). These authors also proposed that the poor colloidal stability and low conductivity of the composite particles were due to the desorption of CTAB... [Pg.199]

Qiu, Y., Zhang, T., Ruegsegger, M., Marchant, R.E. Novel nonionic oligosaccharide surfactant polymers derived from poly(vinylamine) with pendant dextran and hexanoyl groups. Macromolecules 31, 165-171 (1998). doi 10.1021/ma9707401... [Pg.174]

Balomenou I, Bokias G (2005) Water-soluble complexes between cationic surfactants and comb-type copolymers consisting of an anionic backbone and hydrophilic nonionic poly(N, N-dimethylacrylamide) side chains. Langmuir 21 9038-9043. doi 10.1021/la0503505... [Pg.84]

Many reports have appeared regarding complex formation for a variety of systems, such as nonionic and anionic surfactants with sodium carboxy-methylcellulose, anionic and cationic surfactants with nonionic poly-mers, SDS with methylcellulose and polyvinyl alcohol, and SDS with gelatin. Reports have also dealt with such topics as the effect of ionic surfactant counterions on complex formation,the dependence of folding and unfolding of polymers on the extent of binding, and the photochemistry of the complex. ... [Pg.241]

HLB =13) and 20% paraffin oil (HLB = 10). The company you are working for wants to change this emulsifier mixture and use a mixture of nonionic (poly(ethylene oxide)s) surfactants C12E30 and C16E4, of which one is hydrophihc and the other is hydrophobic. How much would you need of the hydrophihc surfactant so that the emulsion has the same characteristics as the original one All concentrations are in weight fractions. [Pg.280]

Ueno et al. [21] studied the antifogging effect of surfactants on transparent cellulose ester films. Nonionic fluorinated surfactants, applied as a monolayer, were more effective antifogging agents than the corresponding nonionic hydrocarbon surfactants. The surfaces of the thin film placed in a closed chamber filled with water vapor at 60°C remained transparent for a long time. The antifogging effect of nonionic fluorinated surfactants was attributed to a double stracture consisting of fluorocarbon and poly(ethylene oxide) chains in the monomolecular layer. [Pg.353]

Antiblocking agents for vulcanized or unvulcanized rubbers have been formulated with a nonionic fluorinated surfactant [279]. Films of poly(vinyl alcohol) or saponified ethylene-vinyl acetate copolymers were treated with a nonionic fluorinated surfactant [C8Fi7S02NRCH2CH20(CH2CH20)ioH to reduce Mction and blocking [280]. [Pg.372]

Because most fluorinated surfactants are commercial products containing several components, the toxicity of impurities in fluorinated surfactants has to be considered. Commercial fluorinated surfactants are usually sold as solutions in an aqueous solvent [10]. In some cases, the solvent may cause more systemic or local toxic effects than the surfactant itself. The solvent and volatile impurities may dominate the toxic effects produced by inhalation. Nonionic surfactants with a poly(oxyethylene) hydrophilic chain may contain 1,4-dioxane, which has shown carcinogenic activity in some animal tests. 1,4-Dioxane is a by-product found in nonionic surfactants, regardless of whether the surfactants are fluorinated. However, the concentration of 1,4-dioxane in nonionic surfactants is carefully controlled and is usually very low (about 0.1% or less). Air monitoring has indicated that at a workplace where there are nonionic fluorinated surfactants containing about 0.1 % dioxane, the 1,4-dioxane concentration in air would be below 1 ppm. [Pg.453]

Schroder [20b] used high-performance liquid chromatography (HPLC)/ mass spectrometric (MS)/MS with a thermospray interface [20c] to detect, identify, and quantify metabolites of Fluowet OTN, a nonionic fluorinated surfactant with the structure R F2,i+iCH2CH2(OCH2CH2)wOH. The biodegradation was limited to the poly(oxyethylene) hydrophile [20b]. The absence of fluoride ions indicated that the perfluorocarbon chain was not degraded. [Pg.460]

Study on the effects of nonelectrolyte additives, 2-butoxyethanol, poly(eth-ylene glycol), and glucose, on various physicochemical aspects of aqueous solutions of two nonionic silicone surfactants based on poly(dimethylsiloxane)-gra/f-... [Pg.8]


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