Physical adsorption at solid-liquid interface is an effective way to dynamically alter the surface properties text/italics{in-situ} and is prevalent in biology, geoscience, biotechnology, catalysis, food processing, agriculture, textiles, coatings, adhesives and lubricants, and cosmetics Over the last century an extensive framework of the thermodynamics and kinetics of adsorption as well as the intermolecular forces that govern the physical interactions between the substrate, solute, and solvent has been established, helping elucidate the structure of adsorbates. However, there lacks an understanding of the connection between the local conformation of the adsorbed molecules and its influence on the macroscopic interfacial phenomena. In this research we have employed vibrational spectroscopy techniques namely the interface-selective non-linear sum frequency generation (SFG) and linear attenuated total reflectance Fourier transform infrared (ATR-FTIR) in conjugation with contact mechanics to develop the molecular level insights into macroscopic phenomena of wetting, adhesion, and sliding friction. We study the interfacial structure of small molecules (surfactants and solvents) as well as macromolecules adsorbed on model surfaces of sapphire (aluminum oxide) and silicone dioxide. Using SFG, we discovered a strongly coordinated ice-like water layer confined between two charged surfaces, under hydration pressures, formed by the adsorption of a cationic surfactant (cetyl trimethyl ammonium bromide, CTAB) on dissimilar hydrophobic surfaces (phenylethyl trichlorosilane, PETS self-assembled monolayer, and polydimethylsiloxane elastomer, PDMS). This strongly coordinated water structure forms past the surfactant concentration needed for a monolayer surface coverage and is observed to reduce the sliding friction. Correlating interface-selective spectroscopy with hydration forces, and their macroscopic manifestation on adhesion and friction requires us to reconsider how we understand water under confinement and its significance in more complicated interfacial processes prevalent in biology, chemistry, and engineering. To investigate the adsorption of a basic polymer (PMMA) on acidic surfaces in carbon tetrachloride (neutral), Chloroform (acidic), and acetone (basic) solvents, we used SFG and ATR-FTIR to build on to the established concept of acid-base interactions that explains limited adsorption from basic and acidic solutions compared to neutral solution due to competitive interactions. We show that besides the differences in adsorbed amount, chains adsorbed from an acidic solvent adopt a flat conformation with a much smaller ratio of segments of loops and tails to trains compared to those adsorbed from a neutral solvent. Surface interaction parameters alone cannot predict the differences in conformation of chains adsorbed from acidic or neutral solvents. Such differences in the static and dynamic conformations have consequences in understanding the exchange kinetics, colloidal stabilization, chromatographic separations, adhesion and friction, and stabilization of nanocomposites. The adsorption of polyelectrolytes driven by Coulombic interactions becomes complicated when mixed with oppositely charged surfactant which modulates the net charge and solubility of polyelectrolytes in water resulting in a characteristic bulk phase diagram. We have investigated the adsorption from pre-mixed solutions of a cationic polysaccharide (PQ10) and the anionic surfactant sodium dodecyl sulfate (SDS), on an amphoteric alumina surface using quartz crystal microbalance with dissipation (QCMD). By tuning the surface charge of the amphoteric alumina, we confirmed the importance of electrostatic interactions on the adsorption on a hydrophilic charged surface, a suggestion that was made earlier solely based on the measurements on negatively charged surfaces. We also directly correlate the bulk phase transitions at the interface adsorption by observing a maximum extent of adsorption on both negatively and positively charged surfaces from a solution corresponding to the maximum turbidity. Using the Voight based viscoelastic model, QCMD also provided information on the viscosity, shear modulus, and thickness of the adsorbed polymeric complex, findings of which were corroborated by underwater atomic force microscopy (AFM) measurements. Shifting gears from adsorption to understanding the polymer thin films surface structure in different environments, we used SFG to observe the surface restructuring of an amphiphilic glassy homopolymer poly(alpha-hydroxy-n-butyl acrylate, PHNB) from hydrophobic to aqueous environment. We observed relative changes in ordering of hydrophobic and hydroxyl pendant groups upon going from air to water at different temperatures showing their impact on wetting of the polymer surface observed by means of dynamic contact angles measurement.

Interfacial Phenomena examines the fundamental properties of various liquid interfaces. This book discusses the physics of surfaces; electrostatic and electrokinetic phenomena; and adsorption at liquid interfaces. The properties of monolayers; reactions at liquid surfaces; diffusion through interfaces; and disperse systems and adhesion are also deliberated. Other topics include the vapor pressures over curved surfaces; electrical capacity of the double layer; applications of electrophoresis; and thermodynamics of adsorption and desorption. The experimental methods of spreading films at the oil-water interface; penetration into monolayers; experiments on dynamic systems; and spontaneous emulsification are likewise covered in this text. This book is beneficial to chemical engineers and students concerned with interfacial phenomena.

The main objective of this volume is to demonstrate the importance of the fundamental aspects of interfacial phenomena in various industrial applications. The text provides the reader with the knowledge that is essential for the composition of the complex multi-phase systems used in the above mentioned areas of application. It should enable the physical and formulation chemist as well as the chemical engineer in designing the formulation on the basis of a rational approach. It will also enable the formulation scientist to better understanding the factors responsible for producing a stable product with optimum application conditions. The book should also be very useful for teaching the subject of formulation at academic institutions.

Since the publication of the first edition of Interfacial Phenomena, the interest in interfaces and surfactants has multiplied, along with their applications. Experimental and theoretical advances have provided scientists with greater insight into the structure, properties, and behavior of surfactant and colloid systems. Emphasizing equil

This fundamental book on interfacial phenomena forms the basis of application of interface and colloid science to various disperse systems. These include suspensions, emulsions, nano-dispersions, wetting, spreading, deposition and adhesion of particles to surfaces. These systems occur in most industrial applications, such as personal care and cosmetic formulations, pharmaceutical systems particularly for controlled and targeted delivery of drugs, agrochemical formulations and enhancement of their biological performance, paints and coatings as well as most food formulations. These applications are described in volume 2. The text is very valuable for formulation chemists, chemical engineers and technologies who are involved in such applications. In addition this fundamental text is also valuable for research scientists and Ph.D. students investigating various aspects of interface and colloid science.

Now in its fourth edition, Surfactants and Interfacial Phenomena explains why and how surfactants operate in interfacial processes (such as foaming, wetting, emulsion formation and detergency), and shows the correlations between a surfactant's chemical structure and its action. Updated and revised to include more modern information, along with additional three chapters on Surfactants in Biology and Biotechnology, Nanotechnology and Surfactants, and Molecular Modeling with Surfactant Systems, this is the premier text on the properties and applications of surfactants. This book provides an easy-to-read, user-friendly resource for industrial chemists and a text for classroom use, and is an unparalleled tool for understanding and applying the latest information on surfactants. Problems are included at the end of each chapter to enhance the reader’s understanding, along with many tables of data that are not compiled elsewhere. Only the minimum mathematics is used in the explanation of topics to make it easy-to-understand and very user friendly.

This English translation of a well-known Japanese book covers interfacial physicochemistry in materials science, especially for iron- and steelmaking processes. Interfacial Physical Chemistry of High-Temperature Melts bridges the gap between the basics and applications of physicochemistry. The book begins with an overview of the fundamentals of interfacial physical chemistry and discusses surface tension, describing the derivation of important equations to guide readers to a deep understanding of the phenomenon. The book then goes on to introduce interfacial properties of high-temperature melts, especially the Marangoni effect, and discusses applications to materials processing at high temperature focusing on recent research results by the author and the co-workers. This book is aimed at researchers, graduate students, and professionals in materials processing. Video clips of in-situ observation including experiments under microgravity condition and x-ray observation are available for download on the publisher's website to allow for a deeper understanding.