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The plots „amount I− adsorbed against pI" on freshly precipitated AgI, mol per mol, are linear. At pI=8 and at pIlimit=9.4−9.1 abrupt changes of the slopes can be observed. The slopes of the plots, i.e. the adsorption capacities are proportional to the logarithm of the starting I− concentration and have common zero points of adsorption. The initial I− concentration determines the number of primary particles formed and the number of I− adsorbed per primary particle, i.e. at the starting I− concentration the number of I− adsorbed is maximal and at the Ag+ concentration at which the isoelectric coagulation sets in the number of I− adsorbed is minimal. The slope of the plots is explained as being proportional to the difference between the maximal and minimal number of I− adsorbed and to the number of primary particles. The slopes of the plots are the higher the lower is the sol concentration and they are the lower the longer were the times elapsed between the precipitation and the measurement. The presence of cations of various valencies in a concentration higher than the critical one for coagulation cause the minimal adsorption capacity. The increase of the cation valency for 1 causes a shift to lower values of the critical concentration which shift is practically equal for the Na+-Ba2+ and Ba2-La3+ pairs. [ABSTRACT FROM AUTHOR]

The expansion of surface tension into an additive series of terms due to the intermolecular forces, originally introduced by Fowkes, is firstly discussed. Based on this expansion, a survey is given on the analytical methods to determine the terms by means of contact angle measurements. An examination on these methods and some results on several organic polymer solids is made, and the surface pressure of adsorbed vapor is estimated. Also assuming the Berthelot's relation on the interfacial energy, a polar term of surface tension is derived from the experimental data, in addition to the non-polar term. As an application of this analysis, the calculated interfacial energy is compared with the shearing adhesive strength between polymeric solids, which is approximated to the static friction. [ABSTRACT FROM AUTHOR]

Pioneering works on regular solutions, electrolyte solutions and (regular) polymer solutions have been done already before 1953. The kinds of intermolecular forces involved and the types of solvents treated in these solutions seem to cover almost all kinds of solutions. Nevertheless, solute and solvent molecules randomly mix by thermal motion in these solutions and the theory also assumes random mixing. These idealized solutions are not general, but rather exceptional among so many solutions which we encounter in our research, i.e., surfactant solutions, biological systems, solutions in the process of manufacturing or in environmental problems, etc. Hence, the study of solutions should be directed now to the more sophisticated, delicate and realistic systems which are not yet well developed. The most striking feature of these solutions may be the dissolution due to the orientation, arrangement, conformation and structure formation of molecules, which are otherwise practically insoluble by random mixing only. The mechanisms of dissolution of micellar solutions of surfactant and water soluble polymers were explained as typical examples. The solubility of these substances in water is very small, but that of water in these substances is infinitely large. The solution resembles to two phases mixture of water and water swollen solute phase for both cases over the concentration range. [ABSTRACT FROM AUTHOR]

Copyright of Colloids & Surfaces is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Both a fully hydroxylated silica (HiSil 233) and a partially hydroxylated silica (Cab-o-Sil M-5) were treated with organosilanes and a silazane. Water adsorption isotherms were then monitored on the resulting products. Reflectance IR spectroscopic measurements were used to follow the reactions of the surface hydroxyls with the silanes and to examine the subsequent water adsorption. The main objective was to ascertain the water susceptibilities of the different functional groups and the availability to water of any residual hydroxyls. The silazane and silances employed were: hexamethyldisilazane, vinyl-trichlorosilane and the alkoxysilanes: γ-glycidoxypropyltrimethoxysilane, 3-mercaptopropyl-trimethyoxysilane and aminopropyltriethoxy-silane. The latter three were reacted from the liquid phase, first hydrolyzing to the silanetriols, with additional complications from condensation reactions. The vinyl compound and the disilazane were reacted from the vapor phase. Sharp difference between the results for the fully hydroxylated and the partially (25%) hydroxylated silica were found. The silanetriols upon heat treatment formed a multilayer polymer network on the latter and only a two-dimensional network on the former apparently due to hydrogen bonding to residual hydroxyls. The reacted silanes formed umbrellas over reacted hydroxyls on the former which were nevertheless available to water molecules. With the latter, however, a much more hydrophobic surface was produced. A number of details were also provided by the reflectance IR measurements. Finally, the following order of susceptibility to water molecules was established, particularly for the treated Cab-o-Sils: [ABSTRACT FROM AUTHOR]

The magnitude of colloidal and mechanical effects of the interaction of clays and water is unusually large, therefore, long range effects of surface forces on the structure of water are often assumed to exist in these systems. However, such effects can be readily explained on the basis of electrical and dispersion forces between the plate-like clay particles, according to a qualitative and quantitative analysis of such forces, and in particular the forces due to the interaction of electrical double layers. Applications in such diverse areas as foundation engineering, land slide analysis, oil drilling fluid management, and ceramics production are briefly discussed as illustrations. Short range interaction — up to about 1 nm — between clay and water does affect the structure of water which is adsorbed on the clay particle surfaces, as is shown by the evaluation of the entropy of adsorption and from IR and NMR studies of water adsorbed by expanding clays. An illustrative application of the quantitative analysis of adsorption forces is an evaluation of the retention of water in shales under overburden pressure. [ABSTRACT FROM AUTHOR]

The methods for preparation of colloidal dispersions of metal hydrous oxides consisting of particles exceedingly uniform in size and shape are described in detail. These sols are, as a rule, prepared by aging acidic solutions of metal salts at elevated temperatures. It is shown that the anions play a decisive role in the particle formation. Electron micrographs of such systems, as obtained from solutions of aluminum, chromium, thorium, titanium, iron, and copper salts, will illustrate that certain metal hydrous oxides appear in the form of spherical (amorphous) particles while others give well defined crystalline particles of different shapes. Certain properties and applications of these new inorganic latices are illustrated and discussed. [ABSTRACT FROM AUTHOR]

The solubility of benzene and toluene in water, and 1, 2, 4 and 8 mol/l urea-water solutions was determined at 5-10 degrees intervals from the freezing point of each solution to 55 °C. The solubilities (N: mole-fraction) were fit to parabolic equations of the form 1 $$\log N = {\rm A}(1/T)^2 + B(1/T) + C.$$ . [1] By differentiating the equation [1] with regard to (1/T) the heat of solution was obtained as follows; $$\Delta {\rm H} = - R[2A(1/T) + B].$$ . The heat of solution consists of two terms, that is, −2A(1/T) R and −BR. The coefficients A and B decreased with increasing the urea concentration in its aqueous solution. From the results the mode of action of urea on the solubility of aromatic hydrocarbons in water was ascribed to its capacities for (1) disrupting iceberg, and (2) reducing the average density of hydrogen bonds and/or making favorable interactions with hydrocarbons. [ABSTRACT FROM AUTHOR]

Dye adsorption spectroscopy has been used as a tool to determine cmc of anionic and cationic surfactants in water. The effect of pH and sodium chloride was examined on cmc. The dye was found to interact with sodium dodecyl sulfate (SDS) micelles but did not interact with cetyltrimethyl ammonium bromide (CTAB). In phosphate buffer and NaCl, the cmc of SDS in presence of dye was greatly lowered. The mode of interaction and the decrease in cmc in presence of dye is discussed in terms of induced micellization. The results were confirmed by conductometric measurement. [ABSTRACT FROM AUTHOR]

The correction to be applied to the apparent particle size as determined microscopically, on account of diffraction of light, has been considered. Two distinct cases viz. amplitude (opaque) and phase (transparent) particles have been considered, the theoretical treatment for the diffraction of light for which cases was available from literature. The treatment has been applied for particle size correction in case of spherical water-suspended particles of silver iodide, nujol, castor oil, iodobenzene and dimethylaniline. [ABSTRACT FROM AUTHOR]

The relation between the partition coefficient (Kp), hydrophilic-lipophilic balance (HLB) and effective chain length (neff) were investigated on the basis of literature data for ionic and nonionic surfactants. The effect of various types of structural modifications on the Kp and HLB of certain surfactants was considered. Using the neff concept for the substituted species, our approach is expected to make possible choice of surfactants for specific purposes in a less arbitrary fashion than up to now. [ABSTRACT FROM AUTHOR]

The effects of initial emulsifier concentration and emulsification time upon the globule size distribution of new type of emulsions, called oil-in-oil emulsions (nonaqueous systems) have been studied. The time of emulsification to reach a steady state globule size increases linearly with increasing initial surfactant concentration, upto an optimum emulsifier concentration, thereafter it remains constant. The initial emulsifier concentration has little effect on the steady state globule size distribution of nonaqueous emulsions. The values of frequency function, geometric standard deviation, geometric mean diameter, mean volumesurface diameter, and globule diameter of most frequent occurrence, of emulsions have been determined. [ABSTRACT FROM AUTHOR]

Electrophoretic mobility measurements have been carried out using droplets of four different oil-in-water emulsions in presence of electrolytes having different valent counterions. For each electrolyte three different (low) concentrations were used; at each concentration mobilities were measured for particles of varying sizes. In this manner mobilities for different values of χa, though presumably at constant values of ζ, were obtained. The ζ potentials were calculated by using the Wiersema-Loeb-Overbeek (W.L.O.) computational method, or failing this, the Overbeek analytical approximation method. Assuming suitable constant values of ζ the particle mobilities were then calculated by W. L. O. method. Also, the particles being fluid in nature, the effect, if any, of the viscosity of the fluid of the particle (rather than of the second order electrical effects such as relaxation correction) on its electrophoretic mobility was also investigated. The Booth liquid drop electrophoresis equations were used to calculate the particle mobilities, assuming suitable constant values of (i) ℵ/ℵ′ and ζ, or (ii) ζ only. In every case, the measured electrophoretic mobilities have been found to increase with increasing particle size. The effect of electrolytes is, in general, to maintain the same trend. Again, the calculated ζ-potentials have been found not to remain constant in solutions of constant electrolyte concentration and composition, but show a steady increase with increasing particle size; this is true for both the distilled water as also the electrolyte solution systems. The calculation of electrophoretic mobility, using the w.L.O. relaxation correction method, on the assumption of a suitable average (constant) value of ζ for each system shows that the calculated mobility values agree generally well with the observed values. Also, among the two liquid drop electrophoresis equations used, the simpler equation based on the assumption of interfacial layer charge distribution is found to be definitely less successful in all cases; it predicts only very slight increase of mobility with particle size. The equation based on the model of a diffuse double layer type of charge distribution inside the liquid droplet is somewhat more successful. [ABSTRACT FROM AUTHOR]

The flocculation of negatively charged benzene-in-water emulsions was governed by various metal cations viz., Na1+, Pb2+, UO22+, Cr3+ and Th4+. The anionic detergents BSS, OSS and SAS were the emulsifying agents. The flocculation studies were made by determining the zeta potentials microelectrophoretically. All the electrolytes except NaNO3 reduced the zeta potential appreciably. However, the charge reversal was observed with Th(NO3)4 only. The flocculating powers of the salts were of the order Th4+>Cr+3>UO2+2>Pb+2>Na+1. The emulsifying powers of the detergents were of the order OSS>SAS>BSS. The results were interpreted in the light of D LVO theory and the flocculation was largely found to occur in secondary minima which is by nature reversible. [ABSTRACT FROM AUTHOR]

Stable oil-in-water emulsions were prepared by the use of aluminium resinate as emulgent. The stability was determined in terms of coagulation which was brought about by inorganic salts with different cations. Coagulation of the emulsion was studied hemocytometrically and electrophoretically. Kinetically coalescence was found to be the rate determining step. Electrophoretic data were recorded as a function of electrolyte concentration. The charge reversal was observed for Th4+, Cr3+, UO22+ and Pb2+ ions. Using particle size, zeta potential and van der Waals constant, as parameters to calculate interaction energies, it was found that the DLVO theory allows satisfactory quantitative interpretation of emulsion stability. Various parameters for cationic binding were calculated at the isoelectric point of the emulsion. [ABSTRACT FROM AUTHOR]

The effect of some cationic surfactants on the stability of the xylene-in-water emulsion stabilized by dodecyl benzene sulphonate has been studied. The globules size was determined microphotographically. The stability of the emulsion system has been assessed by the measurement of electrokinetic potentials in presence of surfactants. The interaction energies have also been calculated and plotted as a function of interparticle distance. Flocculation studies were carried out hemocytometrically and values were correlated with electrokinetic potential. The flocculation and coalescence rate constants were determined separately in order to study the kinetics of coagulation of the system. The nature of adsorption of these surfactants has also been explained by calculating adsorption constants, value of van der Waals constant, number of binding sites, charge density and free energy of adsorption. [ABSTRACT FROM AUTHOR]

Finely dispersed solids specially freshly precipitated hydroxides of polyvalent metals have got the property of promoting oil-in-water emulsions. A study of the hydroxides of 11 metals as emulsifiers reveals that they yield coarse, though very stable emulsions comparable to those stabilized by macromolecules. The emulsion behaviour has been interpreted by studying flocculation, coalescence and the electrokinetic potential. The latter has been studied as a function of electrolyte, complex salts and surfactants both cationic and non-ionic. The stability of the emulsions is attributed to the strength of the interfacial film of the adsorbed hydroxides which is presumably of colloidal dimensions. [ABSTRACT FROM AUTHOR]

The role of W, aryl polyglycol ester, and G 100P, an alkyl phenyl polyglycol ether, on the stability of dilute petroleum ether in water emulsion has been studied in the light of the DLVO theory. The zeta potential of the emulsions flocculated by varying concentrations of different electrolytes, viz., potassium nitrate, strontium nitrate and aluminium ammonium sulphate, has been calculated from the mobility data obtained by a microelectrophoretic technique. With the help of these data, the interaction energy profiles were calculated by summing up the attraction and repulsion energies. The high energy barriers so obtained manifested the stability of both systems. The theoretical degrees of aggregation were calculated for varying Van der Waals constant. The electrolyte flocculation was studied haemocytometrically by counting the number of associated and unassociated droplets, and the degrees of aggregation were calculated. By interpolating the observed degree of aggregation into the theoretical curves the operating Van der Waals constant of both systems was obtained, and found to be 1 × 10−13 erg and 3 × 10−13 erg for the W and G 100P systems respectively. Stabilization due to steric hindrance was also suggested to occur in these systems and was explained by the theory of entropy stabilization. The pH measurements were carried out, and it was found that emulsions stabilized by non-ionic surfactants are not pH sensitive. [ABSTRACT FROM AUTHOR]

The stability and properties of oil-in-water emulsions stabilised by a simple non-ionic surfactant, decyldimethylphosphine oxide (DDPo) and by mixtures of DDPo with poly(vinylalcohol) and electrolytes have been investigated. For emulsion stabilised by surfactant alone the results confirm the idea that it is the high interfacial elasticity arising from adsorbed surfactant that determines stability. The variation of stability with surfactant concentration appeared to arise from the accompanying variation of the interfacial dilational modulus. Unlike simple ionic surfactants it was found that DDPo did not associate with poly(vinylalcohol) and although its addition to pVA solutions greatly improved emulsification, emulsion stability was impaired. Interfacial tension data suggested that the surfactant displaced the polymer from the interface. [ABSTRACT FROM AUTHOR]

Microemulsion regions in the system water-potassium oleate-pentanol-benzene were determined by titration and equilibrium compositions in multiphase areas were analyzed. The results showed the W/O microemulsions be inverse micellar solutions in accordance with earlier results. O/W microemulsions are related to the aqueous micellar solutions but with a more complex structure. At high electrolyte content the inverse micellar solution was in equilibrium with a dilute aqueous solution. The water solubilizing capacity of W/O microemulsions passed through a maximum with increasing soap/alcohol ratio, and excess water gave a phase transition to a lamellar liquid crystal at low electrolyte content of the water. The lamellar liquid crystalline phase showed no extremum of properties at compositions in equilibrium with W/O microemulsion of maximum water solubility and the basis for optimum stability of the inverse micellar solutions at a certain alcohol soap ratio was referred to conditions within the solution. The reason for this maximum solubilization capacity was found not to be related to intermicellar interactions but was confined to intra-micellar conditions. Of these conditions of the electric double layer were decisive. [ABSTRACT FROM AUTHOR]

The temperature induced phase inversion of Groundnut oil-in-water emulsions stabilised by blends of Tween 80 and Dimodan LS is associated with the development of multiple phase emulsion drops (W/O/W emulsion). Drops become progressively more complex in structure as the temperature rises until eventually the emulsions invert to W/O. These changes are attributed to two effects which arise from the decrease in the hydrophilic character of the Tween 80 molecules adsorbed with Dimodan LS molecules around oil drops in the initially formed O/W emulsion. The Tween 80 molecules move into the oil drops where configurational changes release water originally entrapped in the polyoxyethylene coils. This results in modifications to the interfacial layer at higher temperatures so that aqueous phase can permeate through it and into the oil drops. [ABSTRACT FROM AUTHOR]

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The currents measured in oxidized low-density polyethylene after a dc step voltage excitation show maxima in the range of minutes to hours for temperatures between 20 °C and 80 °C and for field strengths between 20 and 200 kV/cm. The current maxima are shifted to shorter times by increasing the field strength or the temperature. The transient currents, which are explained by the build-up of an electronic space charge, allow estimation of effective charge carrier mobilities. [ABSTRACT FROM AUTHOR]

Current transients observed when PE slabs with various electrode arrangements are illuminated are shown to be thermal in origin. In an externally applied field the current is mainly due to capacitive changes, while in zero external field the current from a previously polarized sample is due to nonlinear expansion of the dielectric and the resulting change in the profile of the immobile charge, i.e. field distribution within the sample. The observation of current transients through non-linear expansion (CTNE) of the dielectric thus allows nondestructive detection of arbitrary space charge profiles. [ABSTRACT FROM AUTHOR]

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When treated with adequate abstraction simple principles can be developed for a quantitative characterization of oriented states in unaxially deformed partially crystallized polymer systems dependent on the macroscopic draw ratio. Whatever suggestion of the microscopic processes are made, some general regularities of the orientation-strain relation can be referred to essential properties of the micro-structure in partially-crystallized systems. It can be demonstrated that when an explanation of the orientation-strain relations will be formulated the crystal network model is good for any general understanding of the deformation and the shrinking processes in partially crystallized polymer systems. [ABSTRACT FROM AUTHOR]

Copyright of Mehrphasige Polymersysteme is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The contiguity parameter in a generalization of the Tsai-Halpin equation is suggested as a useful quantitative measurement of the influence of morphology (i.e. size, shape, packing geometry) of heterogeneous regions on mechanical properties. [ABSTRACT FROM AUTHOR]

The influence of added wate on polyoxyethylene dodecyl ethers was investigated by NMR and IR. At 35†C the water was equally distributed among all the groups in the oxyethylene chain, but did not completely surround the ether linkage closest to the alkyl chain until the water concentration was high. At 70 °C the ether formed aggregates as soon as water was added, so that the water never penetrated to the innermost ether linkage. Water added to solutions of trioxyethylene dodecyl ether and octanoic acid containing a complex of about 3 acid and 1 ether molecules caused a removal of the acid from the complex. [ABSTRACT FROM AUTHOR]

An X-rya investigation of aggregate dimensions and local electron densities in micellar systems of sodium octanoate (NaC8) containing normal alcohols has been made, applying Luzzati's spherical micelle model. In aqueous solutions, the solubilizate being pentanol, octanol or decanol, the results indicate aggregates with thick polar layers, i.e., considerable hydration of the micelles. The thickness of the polar layer increases as the length of the hydrocarbon chain of the solubilizate increases. In the case of systems with "inverted" micelles, that is, where water is solubilized in decanol, the influence of the difference in electron density between the solvent (decanol) and the hydrocarbon part of the aggregates has been investigated. The X-ray data indicate relatively large regions with a high electron density in the interior of the "inverted" micelles. This electron density lies between the electron density of water and that of decanol. [ABSTRACT FROM AUTHOR]

The influence of a weakly polar solubilizate, n-decanol, on the stability constants and the aggregation numbers of smaller aggregates and micelles in aqueous sodium valerate (sodium n-pentanoate) solutions has been investigated by potentiometric titrations at 25 °C and constant ionic strength (3 M Na(Cl)). Under these conditions, the aggregation number of the micelles remains constant as decanol is added. However, the stability of the micelles is considerably increased. The smaller aggregates formed by valerate ions do not bind decanol to a measurable extent At the highest concentrations of solubilized decanol investigated the micelles bind 0.5-0.8 mol decanol/mol valerate, implying a considerable increase in micellar weight even though the aggregation number of the penetanoate in the micelles remains constant on addition of decanol. [ABSTRACT FROM AUTHOR]

The liquid isotropic solution regions in the phase diagrams of water, hydrocarbons and tetraethylene glycol dodecyl ether were determined by direct titration. The results showed that at temperatures close to the Phase Inversion Temperature, PIT, separate regions appeared which contained large amounts of solubilized oil and water. The solutions are of importance for phenomena such as microemulsions, surfactant phases and second solubilization regions. [ABSTRACT FROM AUTHOR]

Starting from the structural properties of liquid water and making use of the known bond lengths and coordination types of the hydrogen bonded water molecule, a number of interface phenomena characteristic of systems containing water bridges are derived and discussed. [ABSTRACT FROM AUTHOR]

In emulsion polymerization free radicals generated in the continuous medium enter the monomer/polymer particles at a rate which is governed by either collision or diffusion dynamics. Previously various theories have assumed one or the other model. Two series of experiments are described to test which theory applies. One series involves seeded emulsion polymerization, while the other starts with a perfectly homogenoeus solution. The rate of radical "capture" by the monomer/polymer particles in both series is proportional to the product of particle number and radius, in support of a diffusion-controlled process. The electrostatic interaction between like charged radicals and particles is thought to be negligible, but experimental proof is required. [ABSTRACT FROM AUTHOR]