Relationship of structure to properties in surfactants: II. Efficiency in surface or interfacial tension reduction

The concept of a quantitative measure for the efficiency with which surfactants depress surface or interfacial tension is introduced. It is shown that the quantity, log (1/C)_π=20, where C is the bulk concentration or surfactant required to reduce the surface or interfacial tension by 20 dynes/cm (surface pressure, π=20), is a suitable measure of the efficiency. This quantity is a linear function of the free energy of transfer of the surfactant molecule from the interior of the bulk phase to the interface. The effect upon the efficiency of various structural groupings in both the hydrophobic and hydrophilic portions of the molecule is calculated and the results discussed. From surface and interfacial tension data, it is shown that the free energy decrease involved in the transfer of a −CH₂-group at π=20 to the aqueous solution-air interface is 450–500 cal mole⁻¹ at 25 C; for the aqueous solution-heptane interface, the free energy decrease/−CH₂-group transferred is greater than 427 cal mole⁻¹ at 50 C. Presented at the AOCS Meeting, Philadelphia, September 1974.     

Surfactant properties of purified polyglycerol monolaurates

A series of purified polyglycerol monolaurates (PGML), such as di-, tri-, tetra-, and pentaglycerol monolaurates, were synthesized, and their surfactant properties in aqueous solutions were examined. The surfactant properties of PGML were compared with those of n-dodecyl polyoxyethylene monoethers (C₁₂EO_n) to examine the function of the hydrophilic part of these compounds. The critical micelle concentration (CMC) values and the surface tension at CMC of PGML and C₁₂EO_n increased linearly with an increase in the number of glycerol and oxyethylene units, respectively; the slope of the increase was greater for PGML than C₁₂EO_n. The minimum surface area per molecule of PGML was smaller than that of C₁₂EO_n at the air/aqueous solution interface. The initial foam heights of the surfactants at the CMC increased with an increase in the number of glycerol or oxyethylene units, and the foam heights of PGML were consistently higher and more stable than those of C₁₂EO_n. Detergency depended on a reduction in interfacial tension. Triglycerol monolaurate showed the lowest interfacial tension and the highest detergency among all the surfactants tested. Overall, the PGML showed better performance in all the surfactant properties tested than C₁₂EO_n. It is noteworthy that the surfactant properties of PGML having few glycerol units (di- to tetraglycerol monolaurates) are on par with those of C₁₂EO_n having many oxyethylene units (hexa- and octaoxyethylene). These results suggest that PGML having a secondary hydroxyl group on every glycerol unit of the hydrophilic part could be more hydrophilic than C₁₂EO_n; this characteristic feature guaranteed the superior surfactant properties of PGML.     

Surface active block copolymers: I. The preparation and some surface active properties of block copolymers of tetrahydrofuran and ethylene oxide

A new type of surface active block copolymer (TE type) having the general formula HO(C₂H₄O)_x(CH₂. CH₂CH₂CH₂O)_y-(C₂H₄O)_zH, was obtained by addition of ethylene oxide to polyoxytetramethylene glycols with molecular weight of 1000-3400. TE types in which the polyoxyethylene sections comprised more than 20–25% of the total weight are soluble in water, and the relation between cloud point and oxyethylene content for TE types was similar to that for propylene oxide-ethylene oxide block copolymers (Pluronics). Some surface active properties of TE types were examined in comparison with those of Pluronics and some other surfactants. The surface tension, foaming and antifoaming properties of TE types were comparable to those of Pluronics. Although the wetting power of TE types was poor, their suspending power (for carbon black) was superior to that of Pluronics in both aqueous and nonaqeuous media. The addition of TE types to some conventional detergents enhanced significantly their detergency. TE types showed a remarkable demulsifying action, on addition to some W/O emulsions.     

Perfluoroalkylated fatty acid monoesters of trehalose and sucrose for biomedical applications: Remarkable emulsifying properties of 6-O-[3′-(perfluorooctyl) propanoyl]-trehalose

A new series of perfluoroalkylated fatty acid monoesters of α,α-trehalose and sucrose has been evaluated with respect to their physicochemical and biological properties for possible biomedical use. These water-soluble compounds strongly reduce the water surface tension and fluorocarbon/water interfacial tension. As co-surfactants in perfluorodecalin/Pluronic F-68 type emulsions they significantly increase the stability of these emulsions. Remarkably stable concentrated perfluorodecalin-in-water (50% w/v) emulsions were obtained when the C₈F₁₇CH₂CH₂C(O)-α,α-trehalose monoester was used as the sole surfactant, while no emulsion could be obtained with its maltoside analogue. No significant effect on the growth and viability of Namalva cell cultures and no hemolytic activity on human erythrocytes at concentrations up to 50 g/L were detected for these amphiphiles in spite of their high surface activity. The LD₅₀ was found to be in the range of 250–375 mg/kg of body weighti.v. in mice.     

Surface properties of N-alkanoyl-N-methyl glucamines and related materials

The surface properties [effectiveness of surface tension reduction (γ_CMC) critical micelle concentration (CMC), efficiency of surface tension reduction (pC ₂₀), maximal surface excess concentration (Γ_max), minimal area/molecule at the interface (A _min), and the (CMC/C ₂₀) ratio] of some well-purified N-alkanoyl-N-methyl glucamines and related polyol-based N-methyl amide-type surfactants, having the structural formula RC(O)N(Me)CH₂(CHOH)_xCH₂OH, where RC(O)=undecanoyl, lauroyl, tridecanoyl, myristoyl, and x=1,3, and 4, were investigated at 25°C in distilled water and 0.1 M NaCl. Water solubility of these compounds does not simply depend on the number of hydroxyl groups in the molecule but is associated with the balance between intermolecular hydrogen bonds and hydrogen bonds formed with water molecules. The fundamental interfacial properties, such as CMC and γ_CMC and two thermodynamic parameters, standard free energy of adsorption and standard free energy of micellization, were found to be significantly dependent on the hydrophobic acyl chain rather than on the number of CHOH groups in the hydrophilic moieties. By contrast, the practical performance properties were greatly dependent on the nature of the hydrophilic group. As a whole, these surfactants had desirable foaming properties and efficient wetting abilities. Furthermore, synergism in foaming and wetting abilities was observed in a binary mixture of these surfactants with an alkyloxyethylene sulfate.     

Synthesis, characterization and electrostatic dissipating ability of poly(oxyethylene) block polyesteramides

Poly(oxyethylene)diamines were included in the copolymerization of ethylene glycol and dicarboxylic acids, such as terephthalic, adipic and sebacic acid, to produce a series of hydrophilic polyether-ester-amides. With the addition of poly(oxyethylene)diamines (average molecular weight of 2,000) to PET in the amounts of 3.2, 6.6, 12 and 16 wt%, melting points of these polymers dropped accordingly, from 240 °C to around 227 °C, and the electronic resistivity decreased from 1×10¹³ to approximately 8×10⁸ ohm/sq. For comparison, the introduction of hydrophilic PEG-2000 or a low molecular weight diamine, such as triethyleneglycol diamine, has less effect on electronic resistivity. Molecular weight, polymer rigidity and ageing are other factors affecting the surface resistivity. The degree of hydrophilicity was measured by the moisture absorption of the fibers made from these polyether-ester-amides. A weight gain of 0.96% was observed for 12 wt% poly(oxyethylene)diamine modified polyether-ester-amides in comparison with 0.40% for the unmodified polyethylene terephthalate). These results are explained by a mechanism involving moisture absorption on the polymer surface through the formation of hydrogen bonding with amide and-(OCH₂CH₂)-functionalities on the polymer surface.     

Interfacial energy for solutions of nanoparticles,surfactants, and electrolytes

The addition of surfactants to modify the surface property of nanoparticles (NPs) from hydrophilic to hydrophobic also enhances their interfacial properties. Several approaches were previously proposed to calculate the surface tension/interfacial tension (IFT) for different systems in the presence of NPs, surfactants, and electrolytes. However, most of these approaches are indirect and require several measured parameters. Therefore, a mathematical model is developed here to calculate the surface tension/IFT for these systems. The developed model takes into account the cohesive energy due to the interaction of the surfactant CH₂ groups, the electric double layer effect due to the interaction among the ions of NPs, surfactants, and electrolytes, and the dipole–dipole interaction of NPs and electrolytes. The developed model is compared and validated with the laboratory experimental data in literature. The results reveal further understanding of the mechanisms involved in stabilization of oil/water emulsion in the presence of NPs, surfactants, and electrolytes.     

Solution properties of homogeneous polyglycerol dodecyl ether nonionic surfactants

The synthesis and solution properties of a homologous series of polyglycerol dodecyl ethers (R₁₂G_n) are described. The phase behavior, surface tension, cloud point and HLB value (hydrophile lipophile balance) of these surfactants in aqueous solutions and in mixed solutions of water/oil have been investigated and compared with values for polyoxyethylene dodecyl ether (R₁₂EO_n). The surface tension measurements showed that R₁₂G_n have sufficiently low values of surface tension and critical micellization concentration (cmc) to serve as useful nonionic surfactants. The mesophases appearing in the R₁₂G_n systems were more stable in a high temperature range than the mesophases of the R₁₂EO_n systems. The cloud point and HLB data indicated that addition of one glycerol group was equivalent to the addition of three oxyethylene units, as far as the hydrophilic property was concerned. The phase diagrams of the R₁₂G_n/dodecane/water systems showed that the solubilizing and emulsifying powers of R₁₂G_n were greater than those of R₁₂EO_n. It is concluded that the polyglycerol chain can be even more useful as the hydrophilic part of nonionic surfactants than the conventional oxyethylene chain.     

Synthesis and dipole-dipole interaction-induced mesomorphic behavior of poly(oxyethylene)s containing (n-octylsulfonyl)alkylthiomethyl or (n-octylsulfonyl)alkylsulfonylmethyl side groups

Two series of ((n-octylsulfonyl)alkylthio)methyl-substituted poly(oxyethylene)s ((-OCH₂CHR-)_n, where R=-CH₂S(CH₂)_MSO₂(CH₂)₈H) (OTP-M, M=3,4,5,6,7,9,12), and ((n-octylsulfonyl)alkylsulfonyl)methyl-substituted poly(oxyethylene) ((-OCH₂CHR-)_n, where R=-CH₂SO₂-(CH₂)_MSO₂(CH₂)₈H) (OSP-M, M=3,4,5,6,7,9,12), were synthesized using polymer analogous reactions from poly(epichlorohydrin) to study the effect of dipole-dipole interactions of the sulfone groups (SO₂) on the ordered structures of the poly(oxyethylene) derivatives. The ordered phases of these polymers were studied using polarizing optical microscopy, X-ray diffraction, differential scanning calorimetry and IR spectroscopy. OTP-Ms and OSP-3 showed ordered phases originated from side chain crystallization, while OSP-Ms except OSP-3 showed liquid crystalline behavior. The poly(oxyethylene) derivatives with M=5,6,7 had double-layer structures, while the polymers with M=3,4,9,12 had intercalating double-layer structures at room temperature. The layer structures of the poly(oxyethylene) derivatives were found to be affected by the positions of the side chain sulfone groups which can generate strong dipole-dipole interactions.     

Some Sugar Fatty Ester Ethoxylates as Demulsifiers for Petroleum Sludge

Several ethoxylated sugar fatty ester surfactants were prepared by the reaction of glucose with three fatty acids, namely, adipic, stearic and palmitic acids to produce GA, GS and GP esters. These glucose esters were then ethoxylated by four different molecular weight polyethylene glycols, namely, 400, 1,000, 2,000 and 4,000 mol L^?1. The prepared ethoxylated esters (12 compounds) were characterized by IR and ¹H‐NMR spectroscopy. The surface activity of the prepared compounds was thoroughly studied by measuring the surface tension of different solutions of these compounds at three temperatures, namely 298, 308 and 318 K. From the surface tension‐concentration plots of these compounds some surface properties, such as CMC (critical micelle concentration), Γ_max (maximum surface excess concentration) and A_min (area occupied per molecule) were calculated. The surface properties of the prepared surfactants were correlated to their chemical structure. It was found that the CMC decreases when increasing the molecular weight of polyethylene glycols, whereas A_min increases. Furthermore, the demulsification test was carried out and the results of demulsification efficiency were correlated to the chemical composition of the investigated compounds. Some factors that affect the demulsification efficiency were also considered. The oil phase recovered from the treated sludge was characterized and mixed with fresh crude to improve its API.     

Relationship of structure to properties of surfactants. 15 Isomeric sulfated polyoxyethylenated Guerbet alcohols

The properties at 25°C in aqueous 0.1M NaCl at the aqueous solution/air, aqueous solution/hexadecane, and aqueous solution/hydrophobic solid interfaces of two isomeric Guerbet alcohol-derived surfactants C₈H₁₇CH(C₆H₁₃)CH₂(OC₂H₄)₅SO₄Na, one in which the octyl and hexyl groups are both linear (L isomer), the other in which they are both highly branched (B isomer), have been investigated and compared in some cases with commercial sodium linear dodecylbenzene-sulfonate (LAS). The cmc value increases, the pC₂₀ value decreases, and the ΔG^o _ad value becomes less negative in the order: L isomer—B isomer—LAS. The minimum area/molecule at the aqueous solution/air interface increases in the order: LAS≪L isomer<B isomer. The L isomer is slightly more hydrophobic than the B isomer, and both are considerably more surface-active than LAS. The greater steric inhibition to micellization in the B isomer results in the lowest minimum surface tension. Both isomers have similar minimum interfacial tension values against hexadecane. Unusually small minimum area/molecule values for the two isomers at the aqueous solution/hydrophobic solid interface may indicate multilayer adsorption there. Both isomers are more efficient at reducing the contact angle than LAS. Mixtures of the B isomer with the corresponding unsulfated Guerbet alcohol show only weak interaction between the two. No synergism in surface (or interfacial) tension reduction efficiency or micelle formation exists at either the aqueous solution/air or aqueous solution interface but the mixture does show synergism in surface (or interfacial) tension reduction effectiveness, yielding a surface tension value of 28.2 dynes/cm, and an interfacial tension value of 0.1 dyne/cm against hexadecane. Draves wetting times increase in the order: B isomer<LAS<L isomer, and Ross-Miles initial foam heights decrease in the order B isomer ≈LAS>L isomer. Presented in part at the American Oil Chemists’ Society meeting in Cincinnati, May, 1989.     

Nonionic surfactants derived from a new hydrophobic base

Summary A versatile new class of nonionic surfactants has been prepared essentially from ethylene and propylene oxides. The new products are based upon the discovery that a polyoxypropylene glycol having a molecular weight of approximately 900 or higher will function as the hydrophobic unit of a nonionic surfactant which may presumably be represented as HO (C₂H₄O)_a (C₃H₆O)_b (CH₂O₄)_cH. By selection of a polyoxypropylene glycol having a suitable molecular weight and by adjusting the weight ratio of oxypropylene to oxyethylene units in the product, nonionics have been prepared which range in physical form from liquids to solids which are sufficiently hard that they may be flaked. The possibility of wide variation in the molecular weight of the hydrophobic unit and in the weight ratio of the hydrophobic to hydrophilic units in the molecules allows extensive tailoring of the products to give specific control of properties such as solubility in water, detergency, wetting action, and surface tension lowering. Presented at 25th annual fall meeting, American Oil Chemists' Society, Chicago, Ill., Oct. 8–10, 1951.     

Synthesis of nanoscale hydroxyapatite particles using triton X-100 as an organic modifier

Nano-sized rod like hydroxyapatite (HA) particles were synthesized using Ca(NO₃)₂·4H₂O and (NH₄)₂HPO₄ as precursors with varying contents of non-ionic surfactant viz., p-(1,1,3,3-tetramethylbutyl)phenoxypoly(oxyethylene)glycol (triton X-100) as organic modifer. The crystalline phase, chemical composition, surface area and morphology of the prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), BET surface area analysis, high resolution scanning electron microscopy (HRSEM) and transmission electron microscopy (TEM). The above studies indicate the presence of nanoscale hydroxyapatite (HA) phase. Triton X-100 does not appear to affect the crystallinity of the samples. Increase of BET surface area and the consequent decrease in particle size of HA were observed as a function of surfactant content. Probable mechanism for the role of the surfactant in the synthesis of nanoscale HA has also been discussed.     

How the Influence of Different Salts on Interfacial Properties of Surfactant–Oil–Water Systems at Optimum Formulation Matches the Hofmeister Series Ranking

In this work, we present the effects of salts on sodium dodecyl benzene sulfonate micellization and on the interfacial performance of a sodium dodecyl benzene sulfonate–heptane–brine system at optimum formulation, i.e., hydrophilic–lipophilic deviation (HLD) = 0. In order to do that, interfacial tension and dilational interfacial rheology properties of surfactant–heptane–water systems at optimum formulation are measured using an interfacial spinning drop tensiometer with an oscillating velocity, which can accurately measure interfacial rheology properties at both low and ultralow interfacial tensions. The brines used contain one of the following salts: MgCl₂, CaCl₂, NaCl, NH₄Cl, NaNO₃, CH₃COONa, or Na₂SO₄. We performed a one-dimensional salinity scan with each of these salts to achieve an optimum formulation. In relation to the Hofmeister series, we found that, at optimum formulation, systems with chaotropic ions (NH₄⁺, NO₃⁻) present interfaces with ultralow interfacial tensions, very low dilational modulus, and a low phase angle, whereas kosmotropic ions (Mg²⁺, Ca²⁺, SO₄⁻²) generate high interfacial tension and high rigidity monolayers. Intermediate ions in the Hofmeister series (Na⁺, CH₃COO⁻, Cl⁻) present interfaces with intermediate properties. Furthermore, according to the Hofmeister series, interfaces can be respectively ordered from higher to lower rigidity for surfactant counterions Mg²⁺ > Ca²⁺ > Na⁺ > NH₄⁺ and coions SO₄²⁻ > CH₃COO^– > Cl⁻ > NO₃⁻, which correspond to a salting-out (highest rigidity) and salting-in (lowest rigidity) effect. We observed that counterions have a more significant effect on surfactant–oil–water system properties than those that act as coions.     

Mesogen-jacketed liquid crystalline polymers substituted with oligo(oxyethylene) as peripheral chain

Mesogen-jacketed liquid crystalline polymer (MJLCP) is a typical rod-shaped macromolecule. Its unique molecular architecture allows one to tune the geometric parameters of the macromolecular rod. Moreover, the rod surface chemistry can be controlled by designing the peripheral groups of the lateral mesogens. In previous work in this system, short alkyl chains have been used and the resultant macromolecular rods therefore have a hydrophobic surface. In this paper, we report using oligo(oxyethylene) groups as the peripheral groups of the lateral mesogens. Poly{{2,5-bis[4-methoxyoligo(oxyethylene)phenyl]oxycarbonyl}styene} (PnEOPCS) with different oligo(oxyethylene) chain length has been synthesized. These oligo(oxyethylene) groups led to macromolecular rods with hydrophilic surface. Differential scanning calorimetry, polarized light microscopy, and one-/two-dimensional wide-angle X-ray diffraction experiments were carried out to study the phase structures and phase behaviors of this series of polymer. The existence of flexible polar groups lowered the glass transition temperatures of PnEOPCS. All polymers studied showed supramolecular columnar nematic or hexatic columnar nematic phase, which arose from the parallel alignment of the polymer supramolecular rods. The diameter of the cylindrical building block increased with increasing the length of the oligo(oxyethylene) groups. The macromolecular rod surface can be further tuned by complexation the oligo(oxyethylene) with lithium salts. Detailed study showed that this complexation also tremendously affected the liquid crystalline phase of the polymer.     

Synthesis and Surface Activities of Novel Succinic Acid Monofluoroalkyl Sulfonate Surfactants

Two environmentally friendly succinic acid monofluoroalkyl sulfonate surfactants were synthesized from maleic anhydride and polyethylene glycol mono (1H,1H,7H‐dodecafluoroheptyl) ether, i.e. H(CF₂)₆CH₂OCH₂CH₂OCOCH(SO₃Na)CH₂COOH (FEOS‐1) and H(CF₂)₆CH₂(OCH₂CH₂)₃OCOCH(SO₃Na)CH₂COOH (FEOS‐3). The obtained surfactants were characterized by FT‐IR, ¹H NMR, ¹³C NMR and ¹⁹F NMR in detail. The synthesized fluorinated surfactants have a high thermal stability on the basis of thermogravimetric analysis. Their surface properties were examined and the results show that FEOS‐1 and FEOS‐3 surfactants can reduce the surface tension of water to 25.55 mN m^?1 at 10.25 mmol L^?1 and 21.63 mN m^?1 at 8.33 mmol L^?1, respectively; meanwhile, the introduction of oxyethylene groups enhances the hydrophilicity and micellar forming ability and the longer oxyethylene chains the better surface properties. The Krafft points (K_p) of FEOS‐1 and FEOS‐3 were both below 0 °C, which was lower than perfluoro‐n‐heptanesulfonic acid sodium salt (n‐C₇F₁₅SO₃Na, K_p = 56.5 °C) at a similar length of fluorocarbon chains. Comparison studies on two surfactants above and the conventional fluorocarbon surfactants, perfluorooctanoate of ammonium (PFOA) show that the surfactants have comparable properties to PFOA, thus offering an environmentally friendly synthesizing alternatives to PFOA.     

Tailoring surface properties of cellulose acetate membranes by low‐pressure plasma processing

The aim of this study was to tailor the surface properties of cellulose acetate membranes using low‐pressure plasma processing. Argon (Ar) plasma and Difluoromethane (CH₂F₂) plasma were used to control the surface wettabilities of cellulose acetate membranes. Optical emission spectroscopy was used to examine the various chemical species of low‐pressure plasma processing. In this investigation, the plasma‐treated surfaces were analyzed by X‐ray photoelectron spectroscopy, while changes in morphology and surface roughness were determined with confocal laser scanning microscopy. Ar plasma activation resulted in hydrophilic surface. CH₂F₂ plasma deposited hydrophobic layer onto the cellulose acetate membrane because of strong fluorination of the top layer. The results reveal low‐pressure plasma processing is an effective method to control the surface properties of cellulose acetate membranes. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Facile preparation of amphiphilic oxyethylene-oxypropylene block copolymers by selective triazine coupling

A novel synthetic route for preparing high molecular weight poly(oxyalkylene) block copolymers has been developed by using 2,4,6-trichloro-1,3,5-triazine (cyanuric chloride, cc) as the coupling core. The coupling reaction involves the selective substitutions of oligo(oxyalkylene)-amines onto three chlorides of the triazine ring in a stepwise manner at 0, 25 and 130 °C. By judiciously selecting the starting amines and reaction conditions, one can tailor the copolymer structures with different block configurations (tri-block, multi-block, random and alternating block). The prepared copolymers can have a high molecular weight, up to 25,600 g/mol (GPC polydispersity=1.48), and also high thermal stability due to the presence of triazine functionalities. The copolymers with hydrophilic and hydrophobic oligo(oxyalkylene) blocks are of versatile properties in solubility (water soluble or water insoluble) and morphology (crystalline or amorphous). With a specific structure of alternating oligo(oxyethylene)/oligo(oxypropylene) blocks (2000 g/mol each block), the copolymer exhibits the property of self-association. It reduces the interfacial tension of toluene/water as low as 0.5 dyne/cm at the critical micelle concentration of 0.01 wt%.     

Molecular weight advancement of poly(ethylene ether carbonate) polyols

Poly(ethylene ether carbonate) polyols have been prepared from ethylene carbonate and monoethylene glycol (MEG) or diethylene glycol (DEG) using sodium stannate trihydrate as catalyst. When these polyols (catalyst removed) are heated to elevated temperatures (< 180°C) at reduced Pressures, volatile impurities are removed, as distillate, molecular weight builds in a controllable manner. This is thought to be a transesterification process in which ? OC(O)CH₂CH₂OCH₂CH₂OH end groups on one molecule react with carbonate moieties on a second molecule with loss of DEG. These advanced polyols form rapidly with high CO₂ retention and relatively low polydispersity. This process has been characterized by size exclusion chromatography, quantitative capillary gas chromatography of the distillates, ¹³C-NMR of the products, and alkaline hydrolysis of the products followed by quantification of the resultant glycols. The advanced polyols are largely alternating copolymers of DEG and CO₂. They are valuable polyols for polyurethane fabrication.     

Ion conduction of poly[methoxy oligo (oxyethylene) propylene] synthesized by the Et(Ind)2ZrCl2-MAO catalyst

Poly[methoxy oligo (oxyethylene) propylene] was synthesized by means of the Et(Ind)₂ZrCl₂-MAO catalyst. The ionic conductivity of poly[methoxy oligo (oxyethylene) propylene] with the lithium salt depends on the content of the lithium salt. The temperature dependence of conductivity was determined and the Vogel–Tammann/Hesser–Fulcher (VTF) plot agreed well with theoretical values, confirming the influence of the polymer segmental motion on conductivity. The ionic conductivity as high as 10^−4.7 s/cm can be obtained at room temperature, and this can be increased one or two orders of magnitude by blending the polyelectrolyte with hydroxyl-containing additives such as tetraethylene glycol. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 1397–1400, 1999