Micellar chemistry describes the behavior of surfactant molecules which have both polar and non-polar parts. When dissolved in water, the hydrophobic groups of surfactant molecules distort the water structure and some surfactants aggregate at interfaces with their hydrophobic parts isolated from water. Above a critical concentration called the critical micelle concentration (CMC), surfactant monomers begin to spontaneously assemble into micelle aggregates with their hydrophobic parts shielded from water in the micelle core. Micellar catalysis refers to the acceleration of chemical reactions in solution when surfactants are present above their CMC, as reactions can then proceed within the micelle environment.

1. .

2. Micellar Chemistry:
• The Diphilic Nature Of Surfactant Molecules. Which Contain
Polar(hydrophilic) And Non– Polar(hydrophobic) Parts.
• The Special Features Of Their Structure Gives Special Properties To
These Molecules.
• The Diphilic Nature Of Surfactant Molecules Indicate Their Tendency Of
Gathering At Phase Interfaces, Immersing Their Hydrophilic Part In
Water And Isolating Their Hydrophobic Part From It.
• These Tendency As Certains Their Surface Activity , Their Anility To Be
Adsorbed At The Water Air Interface (A) Water – Oil (B) To Wet, The
Surface Of Hydrophobic Bodies And Form Structure Like Soap Films.

4. Behavior of surfactants:
 When a molecule with amphiphilic structure is dissolved in aqueous
medium, the hydrophobic group distorts the structure of the water.
 As a result of this distortion, some of the surfactant molecules are
expelled to the surfaces of the system with their hydrophobic groups
oriented to minimize contact with the water molecules.

5. Micelle formation:
 Micelle formation
Hunter, Foundations of Colloid Science, p. 572, 1993.

6. Driving force:
Hydrophobic effect
Formation of the micelle No formation of the
micelle
Electrostatic repulsion

7. Surfactant aggregates:

8. CRITICAL MICELLIZATION CONSTANT CMC:
Micelles form by the co-operative binding of monomers to
one another concentrations exceeding rather narrow region is
called the CMC.
After that a large number of micelles formin its solution and
no of properties of the solutions sharply change.

9. CHARACTERISTICS OF CMC:
1)The CMC has been one of the most easily determined
experimentally and useful quantitative characteristics of
solution of surfactants with flexible chains.
2)The methods of determining the CMC are based on that
sharp change in the physico chemical properties of surfactant
solution in the region of the CMC.
3)As micelles do not usually have a surface activity the CMC
can be regarded approximately as the equation concentration
as which the chemistry of surface phenomenon ends and
colloid chemistry begins.

10. Definition
Micellar Catalysis.
The Acceleration Of A Chemical Reaction In
Solution By The Addition Of A Surfactant At A
Concentration Higher Than Its Critical Micelle
Concentration So That The Reaction Can Proceed In
The Environment Of Surfactant Aggregates
( Micelles ).