Dispersions in liquids: suspensions,Dispersions in liquids: suspensions, emulsions, and foams

ACS Short Course April 6 - 7, 2013 New Orleans, LA

Ian MorrisonIan MorrisonLecturer, Harvard University

ian@seas.harvard.edu

Ian Morrison 2010

IanTypewritten Text

Bibliography

Primary text: Morrison, I.D.; Ross, S. Colloidal dispersions: Suspensions, emulsions, and foams; John

Wiley & Sons: New York; 2002. Also suggested: Adamson, A.W.; Gast, A.P. Physical chemistry of surfaces; 6th ed.; John Wiley & Sons:

New York; 1997. Allen, T. Powder sampling and particle size measurement; Elsevier: New York; 2003. Becher, P., Emulsions: Theory and practice, 3rd ed.; Oxford University Press: New York;

2001. Butt, H.-J.; Graf, K.; Kappl, M. Physics and chemistry of interfaces; Wiley-VCH:

Weinheim; 2006. Conley, R.F. Practical dispersion: A guide to understanding and formulating slurries;

VCH Publishers: New York; 1996. de Gennes, P.-G., Brochard-Wyart, F.; Qur, D. Capillarity and wetting phenomena ;

Springer : New York ; 2004. Derjaguin, B.V. Theory of stability of colloids and thin films; Johnston, R.K.. Trans.;

Consultants Bureau: New York; 1989. Dickenson, E.; McClements, D.J.; Advances in Food Colloids; Chapman & Hall: New

York; 1996. Elimelech, M.; Gregory, J.; Jia, X.; Williams, R.A. Particle Deposition and Aggregation;

Measurement, modeling, and simulation; Butterworth-Heinemann: London; 1995. Exerowa, D.; Kruglyakov, P.M. Foam and foam films; Elsevier Publishing: New York;

1998. Goodwin, J. Colloids and interfaces with surfactants and polymers; John Wiley & Sons:

New York; 2004. Gregory, J. Particles in water; CRC Press: Boca Raton, FL; 2006. Holmberg, K.; Jonsson, B.; Kronberg, B.; Lindman, B. Surfactants and polymers in

aqueous solution, 2nd ed.; John Wiley & Sons: New York; 2003. Hunter, R.J. Foundations of colloid science, 2nd ed.; Oxford University Press: New York;

2001. Jenson, W.B. The Lewis acid-base concepts; John Wiley & Sons: New York; 1980. Kissa, E. Dispersions: Characterization, testing, and measurement; Marcel Dekker: New

York; 1999. Napper, D.H. Polymeric stabilization of colloidal dispersions; Academic Press: New

York; 1983. Nelson, Jr., R.D. Dispersing powders in liquids; Elsevier Publishing: New York; 1988. McClements, D.J. Food emulsions: Principles, practice, and techniques, CRC Press:

Boca Taton, FL; 1999. Myers, D. Surfaces, interfaces, and colloids: Principles and applications, 3rd ed.; Wiley-

VCH: New York; 2006. Myers, D. Surfactant science and technology, 3rd edition; Wiley-Interscience: New York;

2006. Norde, W. Colloids and interfaces in life sciences; Marcel Dekker: New York; 2003.

Ian Morrison 2008 Bibliography

Ott, J.-E.; Brandreth, D.A. Small particles technology; Plenum Press: New York; 1998. Pashley, R.M.; Karaman, M.E. Applied colloid and surface chemistry; John Wiley &

Sons: New York; 2004. Povey, M.J.W. Ultrasonic techniques for fluids characterization; Academic Press: New

York; 1997. Rosen, M.J. Surfactants and interfacial phenomena, 3rd ed.; John Wiley & Sons: New

York; 2004. Stein, H.N. The preparation of dispersions in liquids; Marcel Dekker: New York 1996. Takeo, M. Disperse systems; Wiley-VCH; New York; 1999. Whitten, T.A. (with P.A. Pincus) Structured fluids: Polymers, colloids, surfactants;

Oxford University Press: New York; 2004. Williams, RA.; de Jaeger, N.C., Eds. Advances in measurement and control of colloidal

processes; Butterworth-Heinemann: Boston; 1991. Williams, RA., Ed. Colloidal and surface engineering: Applications in the process

industries; Butterworths: Oxford; 1992.

Course lecturesCourselecturesSection Topic Starting Preferred

slide order

1 Surfactantscience andtechnology

3 1

2 Steric stabilization 59

3 Electrostatic stabilization 83

4 Emulsion technology 1034 Emulsion technology 103

5 Foamtechnology 131

6 Wetting andadhesion 163

7 Particle sizingtechniques 197

8 Particlechargeandrheology 219

9 Processing dispersions 235

10 Bibliography 251 x

11 Scalingrelations 253 x

12 Surfactant companies 261 x12 Surfactant companies 261 x

Ice Cream

Ice cream is a:F f i b bbl Foam of air bubbles,

Stabilized with small oil drops,In a matrix that is In a matrix that is,

An emulsion of more oildrops

And a suspension of ice And a suspension of icecrystals,

In a continuous phase ofsurfactants, micelles,su acta ts, ce es,and solutes in water

In a sugar cone.

Ian Morrison 2010

EtymologyEtymologyEnglish Greek Latin English meanings are not literal

translationsoil lipo- oleo- water hydro- aqua- solvent lyo- solvo- both amphi-

translations.

Technical terms (neologisms) are formed by combinations of these wordsboth amphi

flow rheo- affinity -philic lack-of-affinity -phobic nature -pathic

these words.

rheology = science of flowp

science -logy

hydrophilic = with affinity for water lipophilic = with affinity for oil lyophilic = with affinity for the solventlyophilic = with affinity for the solventhydrophobic = lack of water affinity lipophobic = lack of oil affinity lyophobic = lack of affinity for the solvent amphipathic = combining both natures (oil and water understood)

Ian Morrison 2010 Lecture 1: Surfactants 33

amphipathic = combining both natures (oil and water understood)amphiphilic = with affinity for both (oil and water understood)

S f t t i d t h lSurfactant science and technology

Dispersions in liq ids s spensionsDispersions in liquids: suspensions, emulsions, and foams

Ian Morrison 2010

Common surfactant moleculesSodium dodecylsulfate Cetyl trimethyl ammonium bromide

Tweens

Aerosol OT PEO20 sorbitan monolaurate Tween 20 PEO20 sorbitan monopalmitate Tween 40 PEO20 sorbitan mono-oleate Tween 80

Lecithin

C12EO5

PEO20 sorbitan mono oleate Tween 80 PEO20 sorbitan tristerate Tween 65 PEO20 Sorbitan trioleate Tween 85)

Witten Fig 7 1

Ian Morrison 2010 Lecture 1: Surfactants 44

Witten Fig. 7.1

Oil-soluble surfactantsOil soluble surfactantsReactions with fatty acids: Sorbitan monolaurate Span 20 Sorbitan monopalmitate Span 40

Sorbitan mono-oleate (Span 80)

O

Sorbitan monopalmitate Span 40 Sorbitan mono-oleate Span 80 Sorbitan tristerate Span 65 Sorbitan trioleate Span 85

Solsperse 17000O N

O

SO

OO

O

( )nN

SO

OO

O

Polyisobutylene succinimide

Ian Morrison 2010 Lecture 1: Surfactants 55

Instruction Bulletin No. 1How to use your ATLAS HLB kit

The Spans and

W.C. Griffin, Classification of surface-active agents by HLB, J. Soc. Cosmetic Chemists, 1, 311, 1949.

pTweens and blends are recommended standards.

10 gms emulsifier 95 gms oil MixedMixed95 cc waterpH adjusted MixedSit 24 hours

Ian Morrison 2010 Lecture 1: Surfactants 88

Chem Service, Inc. West Chester, PA.

Examples of matching HLB values to application needs

mixing unlike oils together use surfactants with HLBs of 1 to 3use surfactants with HLB s of 1 to 3

making water-in-oil emulsions use surfactants with HLBs of 4 to 6

wetting powders into oilsg p use surfactants with HLBs of 7 to 9

making self emulsifying oils use surfactants with HLBs of 7 to 10

making oil-in-water emulsions use surfactant blends with HLBs of 8 to16

making detergent solutionsuse surfactants with HLBs of 13 to 15 use surfactants with HLBs of 13 to 15

for solubilizing oils ( micro-emulsifying ) into water use surfactant blends with HLBs of 13 to 18

Ian Morrison 2010 Lecture 1: Surfactants 9

www.stephen-herman.com/week_03_08_notes.ppt9

Surfactant adsorption reduces total energy

At the air/liquid interface: And the solid/liquid interface:

Lowers surface tension. Stabilizes dispersions.

Ian Morrison 2010 Lecture 1: Surfactants New page

pDifferent surfactants will be adsorbed at differnent interfaces to different degrees!!

Adsorption at liquid surfaces

Air-water surface Air-oil surface Oil-water interface

Strong adsorption, substantial

Little adsorption, little lowering of surface tension

Strong adsorption, substantial

lowering of surface tension.

surface tension.lowering of interfacial tension.

Ian Morrison 2010 Lecture 1: Surfactants 1313

Adsorption at solid surfacesAdsorption at solid surfaces

The surfactant must be soluble in the liquid!Solid-water interface

Solid-oil surface interface

The adsorption is driven by both strong The adsorption is y gtail/solid interaction and entropy the hydrophobic effect.

driven by strong head group/solid interaction.

Ian Morrison 2010 Lecture 1: Surfactants 1414

Micellization is a dynamic processy p

If micellization is an equilibrium reaction:

KKB B

The law of mass action gives:

[ ][ ]

constantKB

=

[ ][ ]

constantK

K

BB

=

[ ]KB

The value of K can be quite large; for SDS it is about 64. The equilibrium can look like a phase

Adsorption and micellization are competing processes

change (an argument over many years).

Ian Morrison 2010 Lecture 1: Surfactants New page

Adsorption and micellization are competing processes.

Oil surfactants form inverse micelles

Th i llThe micelle core is highly polar. p

The di