Short Course on
SURFACTANTS:
Self-Assembly: Structure-Performance Relationship
For information on next available course date, location and
registration, see the Short Course Website
https://sites.google.com/site/surfactantshortcourse/
or contact:
Emeritus Professor of Chemical Engineering
The Pennsylvania State University
E-Mail: RXN@PSU.EDU
URL: http://www.personal.psu.edu/rxn
Why
this course?
|
Surfactants
find numerous applications in chemical process industries, in the formulation
of pharmaceuticals, household products, and agricultural chemicals, in mineral
processing technologies, and in food processing industries. Naturally
occurring surfactants in plants, animals, and humans have important
biological or physiological functions. The research activity in the
field of surfactants has experienced enormous growth during the last
twenty-five years. More than one thousand research articles are
published annually and many scientific journals are devoted to the study of
surfactants.
The
widespread applications of surfactants originate from the intrinsic duality
in their molecular characteristics; namely, they are composed of a polar head
group that likes water and a non-polar tail group that dislikes water.
Numerous variations are possible in the types of the head groups and tail
groups. This variety in the molecular structure of the
surfactants allows for extensive variation in their solution and interfacial
properties.
One
would naturally like to discover the link between the molecular structure of
the surfactant and its self-assembling and solution properties so that
surfactants can be synthesized or selected specifically for a given
application. This
course is designed for industrial researchers and practitioners interested in
understanding the fundamental solution properties of surfactants and block
copolymers. The course is designed as
a one–day course with approximately eight hours of lectures. |
COURSE SCHEDULE
8:00
AM
INTRODUCTION
8:30
AM
PRINCIPLES OF SELF-ASSEMBLY
9:15
AM
MOLECULAR PACKING PARAMETER
9:45
AM
SURFACTANTS IN AQUEOUS SOLUTIONS
10:45
AM
NOVEL SURFACTANTS - BOLA, GEMINI
11:15
AM
SURFACTANT MIXTURES
Noon LUNCH
1:00
PM SURFACTANTS IN
NON-AQUEOUS SOLUTIONS
1:30
PM SOLUBILIZATION
2:15
PM MICROEMULSIONS
2:45
PM SURFACTANT-POLYMER INTERACTIONS
3:30
PM SELF-ASSEMBLY AT
SOLID-LIQUID INTERFACES
4:15
PM BLOCK COPOLYMERS
IN SOLUTIONS
5:00
PM CONCLUSION
COURSE OUTLINE
INTRODUCTION
TO SURFACTANTS
Classification
of Surfactants
Introduction to Block Copolymers
Phenomenon of Self-Assembly
Critical Micelle Concentration
Aggregate Shapes
PRINCIPLES
OF SELF-ASSEMBLY
Closed
and Continuous Association
Pseudo-Phase Model
Estimation of Critical Micelle Concentration
Estimation of Micelle Size
Size Dispersion of Micelles
Concentration Dependence of Micelle Size
Micelle Charge
Concentration of Surfactant Monomer Beyond
CMC
Sphere-to-Rod Transition
Sphere-to Bilayer Transition
MOLECULAR
PACKING AND SELF-ASSEMBLY
Packing
Requirements
Packing Parameter
Principle of Opposing Forces of Tanford
Packing Parameter Model
Predicting Type of Self-Assembly
SURFACTANTS
IN AQUEOUS SOLUTIONS
Why
Molecules Aggregate?
What Factors Control Aggregate Size and Shape?
Determining Molecular Constants for Surfactants
Influence of Head Groups on Aggregation Behavior
Influence of Tail Groups on Aggregation Behavior
Influence of Ionic Strength on Aggregation Behavior
Influence of Temperature on Aggregation Behavior
Transition from Spherical to Rod-like Micelles
Formation of Vesicles
SURFACTANT
MIXTURES
Ideal
and Non-Ideal Mixed Micelles
Regular Solution Model
Size and Composition Distribution of Aggregates
How Surfactant Composition Affects Mixture Behavior?
Nonionic Hydrocarbon-Nonionic Hydrocarbon Surfactant Mixtures
Ionic Hydrocarbon-Ionic Hydrocarbon Surfactant Mixtures
Ionic Hydrocarbon-Nonionic Hydrocarbon Surfactant Mixtures
Anionic Hydrocarbon-Cationic Hydrocarbon Surfactant Mixtures
Anionic Fluorocarbon-Nonionic Hydrocarbon Surfactant Mixtures
Anionic Hydrocarbon-Anionic Fluorocarbon Surfactant Mixtures
Origin of Ideal and Non-Ideal Mixing Behavior
NOVEL
SURFACTANTS – BOLA AND GEMINI
Description of Bola and Gemini
Surfactants
Modifications to Free Energy
Model
Predicted Aggregation Behavior
Comparison to Classical
Surfactants
SURFACTANTS
IN NON-POLAR SOLVENTS
Differences
Between Water and Non-Polar Solvents
Why Molecules Would Aggregate?
Types of Aggregates
Size Distribution of Aggregates
Question of Existence of a CMC
Influence of Surfactant Molecular Structure
Influence of Temperature
Influence of Solvent Polarity
SURFACTANTS
IN POLAR ORGANIC SOLVENTS
Types of Polar Solvents
Why Surfactants Would Aggregate?
Shape and Size Distribution
Critical Micelle Concentration
Aggregate Size Polydispersity
Concentration-Dependent Aggregate Size
Micelle Formation in Mixed Aqueous-Organic Solvents
SOLUBILIZATION
Phenomenon
of Solubilization
Relations for Solubilizate Uptake in Micelles
Why Solubilization Occurs and What Factors Limit
it?
Solubilization in Ionic Surfactant Solutions
Solubilization in Micelles of Poly(ethylene
oxide) Surfactants
Solubilization-Induced Rod-to-Sphere Transition
Solubilization of Binary Hydrocarbon Mixtures
Solubilization in Mixed Micelles
MICROEMULSIONS
Phenomenon
of Microemulsion Formation
Droplet Microemulsions
Bicontinuous Microemulsions
Phase Diagrams
Size and Composition Dispersion of Droplets
Persistence Length in Bicontinuous Microemulsions
Calculation of Interfacial Tension
Phase Transitions Between Microemulsion
Systems
Nonionic Microemulsions
Microemulsions With Ionic Surfactants
Use of Cosurfactants
POLYMER-SURFACTANT
INTERACTIONS
Interaction
of Nonionic Polymer with Globular Micelles
Interaction of Nonionic Polymer with Rod-like Micelles
Interaction of Nonionic Polymer with Vesicles and Bilayers
Interaction of Nonionic Polymer with Microemulsions
SELF-ASSEMBLY
AT SOLID-LIQUID INTERFACES
Adsorption isotherms at solid-liquid
interfaces
Patterns of aggregation from
AFM studies
Why self-assembly occurs?
Aggregation on Hydrophobic
surfaces
Aggregation on hydrophilic
surfaces
Concentration dependence of
aggregate morphologies
BLOCK
COPOLYMER AGGREGATES
Structure of Block Copolymers
Aggregation of AB, ABA, BAB, and ABC Type Block Copolymers
Why Molecules Aggregate?
What Factors Control Micelle Size?
What Factors Determine Amount of Solubilization?
Block Copolymer Composition and Aggregate Shapes
Solution Conditions and Aggregate Shape
Aggregate Shape Transitions Induced by Solubilization
Phase Behavior of Block Copolymer-Oil-Water System
Comparison to Conventional Surfactants
CONCLUDING
DISCUSSIONS