1. CHM 585 / 490
Chapter 5

2. Chapter 5 Polystyrene PET Addition polymerization
Condensation Polymerization

3. Polystyrene

4. How many “mers”
Monomer
Dimer
Trimer
Oligomer
Polymer

5. Polystyrene

6. Polystyrene

11. Dow polystyrene plants

12. Polystyrene is a vinyl polymer
made from vinyl monomers; that is, small molecules containing carbon-carbon double bonds.
simplest vinyl polymer, polyethylene is made from ethylene

14. Addition Polymerization
Addition polymerization if the entire monomer molecule becomes part of the polymer.
Polystyrene is made by an addition polymerization
Similarly polyethylene, polypropylene, and other vinyl polymers are addition polymers

15. Esterification

16. Esterification / Condensation

19. Polyethylene Terephthalate Condensation Polymer

20. Transesterification

21. PET by Transesterification

22. PET by Transesterification
DMT is a distillable material
Can be purified
Melts at 140 C
Can be shipped and transferred as a liquid

23. Catalysis
Esterifications and transesterifications are acid catalyzed reactions.
But!!!!!
What else is an acid catalyzed reaction?

24. Ether Formation
Acid catalyzed dehydration of alcohols

25. PET catalysts Typically not: Common catalysts: Often combinations used
H2SO4, H3PO4
Common catalysts:
Zinc acetate, Sb2O3, Ti(OR)4
Often combinations used
Leave in catalyst