Colloid Science: Principles, Methods and Applications

400 Pages·2010·17.1 MB·English

by  Terence Cosgrove

Colloid Science
Principles, methods
and applications
Second Edition
Edited by
TERENCE COSGROVE
School of Chemistry, University of Bristol,
Bristol, UK

Colloid Science
Principles, methods
and applications
Second Edition

Colloid Science
Principles, methods
and applications
Second Edition
Edited by
TERENCE COSGROVE
School of Chemistry, University of Bristol,
Bristol, UK
Thiseditionfirstpublished2010
(cid:1)2010JohnWiley&SonsLtd
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LibraryofCongressCataloging-in-PublicationData
Colloidscience:principles,methodsandapplications/editedbyTerence
Cosgrove.–2nded.
p.cm.
Includesbibliographicalreferencesandindex.
ISBN978-1-4443-2019-0(cloth)–ISBN978-1-4443-2020-6(pbk.)
1.Colloids.I.Cosgrove,T.(Terence)
QD549C5852010
541’.345–dc22
2009045994
AcataloguerecordforthisbookisavailablefromtheBritishLibrary.
ISBNHB:9781444320190
ISBNPB:9781444320206
Setin10/12pt,TimesRomanbyThomsonDigital,Noida,India
PrintedandboundinGreatBritainbyCPIAntonyRowe,Chippenham,Wiltshire
This book isdedicatedtothe memoriesof Professor Douglas Everett
and Professor Ron Ottewill whowere an inspiration tomany
generations ofaspiring ColloidScientists.

Contents
Preface xv
Introduction xvii
Acknowledgements xix
List ofContributors xxi
1 An Introduction toColloids 1
Roy Hughes
1.1 Introduction 1
1.2 Basic Definitions 5
1.2.1 Concentration 5
1.2.2 Interfacial Area 10
1.2.3 EffectiveConcentrations 11
1.2.4 AverageSeparation 12
1.3 Stability 14
1.3.1 Quiescent Systems 15
1.3.2 Sedimentation orCreaming 16
1.3.3 ShearingFlows 17
1.3.4 Other Forms ofInstability 17
1.4 ColloidFrontiers 18
References 20
2 Chargein Colloidal Systems 23
David Ferminand Jason Riley
2.1 Introduction 23
2.2 The Origin ofSurface Charge 24
2.2.1 Ionisation ofSurface Groups 24
2.2.2 Ion Adsorption 25
2.2.3 Dissolutionof Ionic Solids 25
2.2.4 Isomorphous Substitution 25
2.2.5 Potential Determining Ions 25
2.3 The Electrochemical Double Layer 26
2.3.1 The Stern–Gouy–Chapman (SGC) Model ofthe Double Layer 26
2.3.2 The Double Layer at the Hg/Electrolyte Interface 30
2.3.3 Specific Adsorption 34
2.3.4 Interparticle Forces 36
viii Contents
2.4 Electrokinetic Properties 36
2.4.1 ElectrolyteFlow 36
2.4.2 StreamingPotential Measurements 37
2.4.3 Electro-osmosis 38
2.4.4 Electrophoresis 39
2.4.5 Electroacoustic Technique 42
References 42
3 StabilityofCharge-stabilised Colloids 45
JohnEastman
3.1 Introduction 45
3.2 The ColloidalPair Potential 46
3.2.1 AttractiveForces 46
3.2.2 Electrostatic Repulsion 47
3.2.3 Effect ofParticleConcentration 49
3.2.4 Total Potential 50
3.3 Criteria for Stability 51
3.3.1 Salt Concentration 51
3.3.2 Counter-ion Valency 52
3.3.3 Zeta Potential 54
3.3.4 Particle Size 54
3.4 Kineticsof Coagulation 55
3.4.1 Diffusion-limitedRapid Coagulation 55
3.4.2 Interaction-limited Coagulation 56
3.4.3 Experimental Determination ofc.c.c. 57
3.5 Conclusions 58
References 59
4 Surfactant Aggregation and Adsorption atInterfaces 61
Julian Eastoe
4.1 Introduction 61
4.2 Characteristic Features of Surfactants 61
4.3 Classification andApplications ofSurfactants 62
4.3.1 Types ofSurfactants 62
4.3.2 Surfactant Uses andDevelopment 64
4.4 AdsorptionofSurfactants at Interfaces 66
4.4.1 Surface Tension and Surface Activity 66
4.4.2 Surface Excess and Thermodynamics ofAdsorption 67
4.4.3 Efficiency andEffectivenessofSurfactant Adsorption 71
4.5 Surfactant Solubility 73
4.5.1 The Krafft Temperature 73
4.5.2 The Cloud Point 74
4.6 Micellisation 75
4.6.1 Thermodynamics ofMicellisation 75