This book considers the different concepts of hydrophile-lipophile balance (HLB) of surfactants and solid particles and the main physicochemical properties of surfactant and solid interfaces which are used to definite the hydrophile-lipophile balance. The book comprehensively analyses all interfacial and bulk properties of surfactants used for the determination of HLB (such as interfacial tension, distribution coefficient, adsorption, surface pressure, surfactants solubility, structure characteristics, distribution between heteropolar phases, micellar formation, chromatographic characteristics, phase separation in emulsions, phase inversion temperature, formation of three phase systems).
The central point of the book is the energetic interpretation of the balance, i.e. the hydrophile-lipophile ratio. At the same time the HLB-number systems of Griffin and Davies and other independant methods of the hydrophile-lipophile balance definitions are discussed: PIT, polarity indexes, surfactant affinity difference etc. The possibility of application of the different characteristics of the hydrophile-lipophile balance as a criterion of phase inversion in emulsions and microemulsion systems water-oil-surfactant are considered.
For the first time the different methods of the hydrophile-lilophile balance definition for solid particles in compact and dispersed form are suggested by the author. The use of hydrophile-lipophile characteristics of solid particles as a criterion of phase inversion in emulsion stabilisation and for other applications is discussed.
For chemists, biologists, engineers and undergraduates interested in colloid dispersions, colloid stability, surfactants and polymers, surfaces and interfaces, technological applications, and environmental colloid science.
Hydrophile - Lipophile Balance of Surfactants and Solid Particles, 1st Edition
Preface. Introduction. Physicochemical properties of surfactants used in the definition of hydrophile-lipophile balance.
Classification of surfactants with respect to structure and chemical nature. Surface-related properties of surfactants. Bulk properties of surfactants. The contributions to Gibbs' energy corresponding to the transfer of surfactant molecules from bulk phases to interfaces as compared to the transfer to other bulk phases. The interpretation of Traube's rule. Brief review of surfactant chromatography. References. Stabilising ability of surfactants in emulsification and foam formation.
Physicochemical properties of emulsion films. Kinetics of flocculation and coalescence. Phase inversion in emulsions. Effect of temperature on emulsion stability - phase inversion temperature PIT. Relation between foam stability and hydrophile-lipophile balance. References. Hydrophile-lipophile balance of surfactants.
Griffin's system of HLB numbers. Kinetic and thermodynamic rationalisation of HLB numbers - Davies' HLBD
number. Critical micellisation concentration and HLB numbers. Phase inversion temperature in emulsion - measure of hydrophile-lipophile
balance. Hydrophile-lipophile balance and chromatographic characteristics of surfactants. Comparative analysis of Griffin's and Davies' HLB numbers, consideration of the influence of the medium and the surfactant structure
on the HLB number systems. Thermodynamic approaches to the determination of hydrophile-lipophile balance. Hydrophile-oleophile ratio determined from the micellisation energy. Hydrophile-lipophile balance and phase inversion of emulsions. Hydrophilic-oleophilic ratio and the formation of micellar systems (surfactant phases). References. Hydrophile-lipophile balance of solid particles.
Behaviour of drops at solid surfaces, and solid spherical particles at liquid/liquid interface. Stabilisation of emulsions by solid particles. Work of wetting and determination of the hydrophile-lipophile balance for solid particles. Calculation of the hydrophile-lipophile balance for highly disperse solid emulsifiers. The dependence of emulsion stability on the work of wetting of emulsifier particles. HLB used as criterion of phase inversion in emulsions stabilised by solid particles. References. Examples of the implementation of hydrophilicity-lipophility concepts in the development of the formulations of surfactants and selection of solid particles for certain purposes.
Physicochemical properties of microemulsion systems. Emulsion systems and emulsion technologies. Use of microemulsion systems for enhanced oil recovery from reservoirs. Breakdown of dilute emulsions. Hydrophile-lipophile balance and foaming properties of microemulsions.
Hydrophile-lipophile balance and selection of reagents in the processes of surface (foam) separation of dissolved substances, colloid particles and oil drops. Hydrophile-lipophile balance and sanitary-technical characteristics of
surfactants. Hydrophile-lipophile balance and protein structure. Use of the hydrophile-lipophile balance concept for the characterisation of solid surfaces with respect to its application. References. List of symbols. Abbreviations of surfactants and surfactant mixtures.
Acronyms. Subject index.