摘要:

Type III microemulsions composed of anionic surfactant, non-ionic surfactant, water, oil, and sodium chloride were studied as a function of the anionic/total surfactant ratio. The activity coefficient of each of the five components in the microemulsion phase was determined. The activity coefficients of the surfactant components in the microemulsions were also computed on a surfactant-only basis. There is substantial negative deviation from ideality of mixing between the dissimilar surfactants. Regular solution theory provides a poor description of the surfactant interaction. In order to test the practical utility of using anionic/nonionic surfactant mixtures in enhanced oil recovery, systems containing alcohol were studied to cover the entire range of surfactant compositions. The optimal salinity and solubilization parameter for the mixtures were found to be similar to the values for systems containing the single surfactants of which the mixture is composed.

ISSN:0193-2691    

DOI:10.1080/01932698608943453

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A new method to measure by means of mercury porosimetry the effective pigment volume concentration has been used to investigate an aspect of the dispersion process of magnetic pigments. The aggregate density, the parameter for describing the effective PVC, has been correlated with a few, mainly magnetic, properties of the coatings.

ISSN:0193-2691    

DOI:10.1080/01932698608943454

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The effectiveness of kneaders in the dispersion process of metal powder pigments has been investigated. Measurements of the aggregate density of the pigments reclaimed from the lacquers show that the magnetic and mechanical deficiencies of metal powder tapes prepared by conventional dispersion processes, e.g. pearl milling, are due to a relatively low aggregate density of the MP pigment. It was found that the aggregate density could be increased very much by introducing a kneader step in the dispersion process.

ISSN:0193-2691    

DOI:10.1080/01932698608943455

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Dilute aqueous “solutions” of anionic surfactants injected during enhanced oil recovery processes usually contain liquid crystalline material. Phase behavior has been studied in a model system containing sodium chloride brine with surfactant, alcohol, and salt contents maintained below 6, 10, and 3 weight percent respectively. Pseudoternary phase diagrams at constant salinities are used to represent the results. Some interpretation of the results is given in terms of micellar shape transformations produced by changes in the relative hydrophilic and hydrophobic properties of surfactant-alcohol mixtures.

ISSN:0193-2691    

DOI:10.1080/01932698608943456

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A new non-intrusive, Instantaneous technique to monitor the creaming/sedimentation of colloidal dispersions is reported. Here the technique is used to determine the detailed concentration profiles of water-continuous emulsions as a function of height and time. The emulsions consist of hexadecane stabilised by nonionic surfactant (Brij 35) In water In the presence and absence of a polysaccharide thickener (hydroxyethylcellulose). The technique involves the measurement of the velocity of ultrasound through the emulsion, which depends simply on the velocity through the individual phases and the bulk composition of the emulsion (provided the individual droplets are smaller than the wavelength of the ultrasound). Applications of the technique may include In-line monitoring of composition during the processing of dispersions and predictive testing of dispersion stability (shelf-life).

ISSN:0193-2691    

DOI:10.1080/01932698608943457

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Polymerization was carried out with surfactant-styrene-brine systems which were formulated for the attainement of ultra-low interfacial tension and three-phase behavior. An anionic-nonionic surfactant mixture was used to maintain the optimum formulation over a certain range of temperature. Dispersion polymerization experiments were carried out with the initiator either in water (persulfate) or in styrene (AIBN). The polymerization systems exhibited both rate of polymerization and molecular weight dependence on the amount of added initiator, but no autoacceleration was observed.

ISSN:0193-2691    

DOI:10.1080/01932698608943458

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor