Emulsions and Microemulsions Flashcards
1
Q
Def of emulsions:
A
system with 2 immiscible liquid phases
- one is in the other as fine droplets
- unstable
2
Q
What is the 3rd component of emulsions?
A
emulsifying agent (aka surfactant) - used to stabilize E
3
Q
Emulsions can be both…
A
water or oil soluble
4
Q
What are the two main types of emulsions?
A
o/w and w/o
5
Q
What are the 3 theories of emulsions?
A
- oriented wedge theory
- plastic/interfacial film theory
- surface tension theory
6
Q
What is the surface tension theory?
A
SAA added and repellent forces between 2 immiscible liquids decrease
7
Q
What are the function of surfactants?
A
lowers each liquid’s attraction to its own molecule
- breaks up large molecules
- takes molecules longer to coalesce
8
Q
Dispersed phase is also known as…
A
- internal phase
- discontinuous
9
Q
Dispersion medium is also known as…
A
- external phase
- continuous
10
Q
Emulsifying agents should be…
A
- compatible with all ingredients in the mixture
- stable
- capable of promoting emulsification (most important)
