Introduction to Applied Colloid and Surface Chemistry

Colloid and Surface Chemistry is a subject of immense importance and implications both to our everyday life and numerous industrial sectors, ranging from coatings and materials to medicine and biotechnology. How do detergents really clean? (Why can't we just use water?) Why is milk "milky"? Why do we use eggs so often for making sauces? Can we deliver drugs in better and controlled ways? Coating industries wish to manufacture improved coatings e.g. for providing corrosion resistance, which are also environmentally friendly i.e. less based on organic solvents and if possible exclusively on water. Food companies want to develop healthy, tasty but also long-lasting food products which appeal to the environmental authorities and the consumer. Detergent and enzyme companies are working to develop improved formulations which clean more persistent stains, at lower temperatures and amounts, to the benefit of both the environment and our pocket. Cosmetics is also big business! Creams, lotions and other personal care products are really just complex emulsions. All of the above can be explained by the principles and methods of colloid and surface chemistry. A course on this topic is truly valuable to chemists, chemical engineers, biologists, material and food scientists and many more.

Auteur

Georgios M. Kontogeorgis and Søren Kiil are both at the Technical University of Denmark, in the Dept of Chemical and Biochemical Engineering. Kontogeorgis is Professor of Applied Thermodynamics, and Kiil is Associate Professor in Coatings Science and Engineering.
Prof Kontogeorgis has been teaching the colloid and surface chemistry course for 12 years, for the past 3 co-teaching with Kiil. Both authors have diverse research interests in strongly interconnected fields. Kontogeorgis' research interests are in the fields of thermodynamics, physical chemistry (especially surface science and polymers), while Kiil's interests are primarily in coatings science and engineering (antifouling-, anticorrosive-, wind turbine blades etc).
Both have valuable books publishing experience: Kontogeorgis most recently on thermodynamic models (2010, Wiley); and Kiil has co-authored a textbook on product design (2007, Wiley).

Contenu

Preface xi

Useful Constants xvi

Symbols and Some Basic Abbreviations xvii

About the Companion Web Site xx

1 Introduction to Colloid and Surface Chemistry 1

1.1 What are the colloids and interfaces? Why are they important? Why do we study them together? 1

1.1.1 Colloids and interfaces 3

1.2 Applications 4

1.3 Three ways of classifying the colloids 5

1.4 How to prepare colloid systems 6

1.5 Key properties of colloids 7

1.6 Concluding remarks 7

Appendix 1.1 8

Problems 9

References 10

2 Intermolecular and Interparticle Forces 11

2.1 Introduction Why and which forces are of importance in colloid and surface chemistry? 11

2.2 Two important long-range forces between molecules 12

2.3 The van der Waals forces 15

2.3.1 Van der Waals forces between molecules 15

2.3.2 Forces between particles and surfaces 16

2.3.3 Importance of the van der Waals forces 21

2.4 Concluding remarks 25

Appendix 2.1 A note on the uniqueness of the water molecule and some of the recent debates on water structure and peculiar properties 26

References for the Appendix 2.1 28

Problems 29

References 33

3 Surface and Interfacial Tensions Principles and Estimation Methods 34

3.1 Introduction 34

3.2 Concept of surface tension applications 34

3.3 Interfacial tensions, work of adhesion and spreading 39

3.3.1 Interfacial tensions 39

3.3.2 Work of adhesion and cohesion 43

3.3.3 Spreading coefficient in liquidliquid interfaces 44

3.4 Measurement and estimation methods for surface tensions 45

3.4.1 The parachor method 46

3.4.2 Other methods 48

3.5 Measurement and estimation methods for interfacial tensions 50

3.5.1 Direct theories (GirifalcoGood and Neumann) 51

3.5.2 Early surface component theories (Fowkes, OwensWendt, Hansen/Skaarup) 52

3.5.3 Acidbase theory of van OssGood (van Oss et al., 1987) possibly the best theory to-date 57

3.5.4 Discussion 59

3.6 Summary 60

Appendix 3.1 Hansen solubility parameters (HSP) for selected solvents 61

Appendix 3.2 The parameter of the GirifalcoGood equation (Equation 3.16) for liquidliquid interfaces. Data from Girifalco and Good (1957, 1960) 66

Problems 67

References 72

4 Fundamental Equations in Colloid and Surface Science 74

4.1 Introduction 74

4.2 The Young equation of contact angle 74

4.2.1 Contact angle, spreading pressure and work of adhesion for solidliquid interfaces 74

4.2.2 Validity of the Young equation 77

4.2.3 Complexity of solid surfaces and effects on contact angle 78

4.3 YoungLaplace equation for the pressure difference across a curved surface 79

4.4 Kelvin equation for the vapour pressure, P, of a droplet (curved surface) over the ordinary vapour pressure Psat for a flat surface 80

4.4.1 Applications of the Kelvin equation 81

4.5 The Gibbs adsorption equation 82

4.6 Applications of the Gibbs equation (adsorption, monolayers, molecular weight of proteins) 83

4.7 Monolayers 86

4.8 Conclusions 89

Appendix 4.1 Derivation of the YoungLaplace equation 90

Appendix 4.2 Derivation of the Kelvin equation 91

Appendix 4.3 Derivation of the Gibbs adsorption equation 91

Problems 93

References 95

5 Surfactants and Self-assembly. Detergents and Cleaning 96

5.1 Introduction to surfactants basic properties, self-assembly and critical packing parameter (CPP) 96

5.2 Micelles and critical micelle concentration (CMC) 99

5.3 Micellization theories and key parameters 106

5.4 Surfactants and cleaning (detergency) 112

5.5 Other applications of surfactants 113

5.6 Concluding remarks 114

Appendix 5.1 Useful relationships from geometry 115 &...