Addition Polymerization Flashcards
1
Q
What are the three steps in polymerization?
A
- Creation of an active site/ initiation stage
- Propagation stage
- Termination
2
Q
Methods of terminating a growing polymer?
A
- Combination of two growing polymers.
- Termination by disproportionate: The combination of two growing radicals to form a dead polymer and byproducts with the release of hydrogen.
2
Q
Types of initiators/ Free radical generators
A
- Free radical generators (largely peroxides)
- Ions
- Co-ordination
3
Q
What is propagation?
A
Propagation is the quick and progressive addition of a monomer to a growing chain.
3
Q
The Free Radical Polymerization Model?
A
Rp = Kp.[Kd/Ktc]^0.5.[I]^0.5.[M]
4
Q
Methods of Activation/Initiation of an addition polymerization reaction?
A
- Use of initiator
a. Free radical generators
b. Use of ionic generators.
c. Co-ordination - Use of redox generators
- Use of high energy radiation
- Thermal or photochemical initiation
5
Q
Steps involved in the kinetics of free radical polymerization
A
- Initiation
a. Homolysis
b. Bonding of free radical - Propagation
- Termination