1. Synthetic and Biological Polymers
Polymers: Macromolecules formed by the covalent attachment of a set of small molecules termed monomers.
Polymers are classified as:
(1) Man-made or synthetic polymers that are synthesized in the laboratory;
(2) Biological polymer that are found in nature.
Synthetic polymers: nylon, poly-ethylene, poly-styrene
Biological polymers: DNA, proteins, carbohydrates

2. Hydrocarbons ex: Alkanes
1 – Meth-
2 – Eth-
3 – Prop-
4 – But-
5 – Pent-
6 – Hex-
7 – Hept-
8 – Oct-
9 – Non-
10 – Dec-
11 – Undec-
12 – Dodec-

3. Hydrocarbons at Room Temperature
Gas
Methane
Ethane
Propane
Butane
Liquid
Waxy
Plastic
20 to 40 Carbons
40 or more Carbons
5 to 19 Carbons

4. Melting Point
As the length of hydrocarbons get longer, the Melting Point grows Higher Why?

5. What other material properties change?
Viscosity
Hardness
Toughness
Flammability

6. Bonding
Covalent
Ionic (NaCl)
Polar (H2O)
Van der Waals

7. Methods for making polymers
Addition polymerization and condensation polymerization
Addition polymerization: monomers react to form a polymer without net loss of atoms.
Most common form: free radical chain reaction of ethylenes
n monomers
one polymer molecule

8. Example of addition polymers

9. Free-Radical AdditionPolymerization of Ethylene
H2C
CH2
200 °C
2000 atm O2
peroxides
CH2
polyethylene 6

10. Free-Radical Polymerization of Propene
H2C
CHCH3 CH
CH3
polypropylene 6

11. .. RO
Mechanism •
H2C
CHCH3 7

12. ..
RO:
Mechanism
H2C
CHCH3 • 9

13. ..
RO:
Mechanism
H2C
CHCH3 •
CHCH3
H2C 10

14. ..
RO:
Mechanism
H2C
CHCH3
H2C
CHCH3 • 10

15. ..
RO:
Mechanism
H2C
CHCH3
H2C
CHCH3
CHCH3
H2C • 10

16. ..
RO:
Mechanism
H2C
CHCH3
H2C
CHCH3
H2C
CHCH3 • 10

17. ..
RO:
Mechanism
H2C
CHCH3
H2C
CHCH3
H2C
CHCH3
CHCH3
H2C • 10

18. Likewise... H2C=CHCl polyvinyl chloride H2C=CHC6H5 polystyrene
F2C=CF Teflon 19

19. Important constitutions for synthetic polymers

20. Supramolecular structure of polymers

21. Structural properties of linear polymers: conformational flexibility and strength

22. Molecular Structure of Polymers
Linear
High Density Polyethylene (HDPE), PVC, Nylon, Cotton
Branched
Low Density
Polyethylene (LDPE)
Cross-linked
Rubber
Network
Kevlar, Epoxy

23. Low-Density Polyethylene (LDPE)
Chain Length:
Low-Density Polyethylene (LDPE)

24. PVC – (polyvinyl chloride)
Chain Length: 4,000 – 5,000
More Polar  Stronger Bonding

25. High-Density Polyethylene (HDPE)
Chain Length: 10,000 – 100,000
High-Density Polyethylene (HDPE)

26. Ultra-high-molecular-weight polyethylene (UHMWPE)
Chain Length: 2-6 million
Ultra-high-molecular-weight polyethylene (UHMWPE)
Joint Replacement
Helmet
Gears

27. Rubber Tree Sap: Goodyear Sticky Viscous Gooey Experiment Luck
Profit ($0)

28. Vulcanization

29. Condensation polymerization
Condensation polymerization: the polymer grows from monomers by splitting off a small molecule such as water or carbon dioxide.
Example: formation of amide links and loss of water
Monomers
First unit of polymer + H2O

30. Polyethylene Terephthalate (PETE) “Polyester”
Chain Length: 4,000 – 8,000
Polyethylene Terephthalate (PETE) “Polyester”
Ester

31. Kevlar
Strong Network of Covalent Bonds
And Polar Hydrogen Bonds

33. Nylon

34. Hydrogen bonds between chains
Supramolecular
Structure of nylon
Intermolecular hydrogen bonds give nylon enormous tensile strength

35. Biopolymers
Nucleic acid polymers (DNA, RNA)
Amino acids polymers (Proteins)
Sugar polymers (Carbohydrates)
Genetic information for the cell: DNA
Structural strength and catalysis: Proteins
Energy source: Carbohydrates

36. Proteins: amino acid monomers
The basic structure of an amino acid monomer
The difference between amino acids is the R group 4

37. Cotton Long Strands of Cellulose + Hydrogen Bonds
Cellulose is the most common organic material on earth!
It is also a primary constituent of wood and paper.

38. Polymers in Biology
Starch
DNA
Sugar
Proteins

40. Proteins: condensation polymers
Formed by condensation polymerization of amino acids
Monomers: 20 essential amino acids
General structure of an amino acid
R is the only variable group
Glycine (R = H) Glycine
First step toward poly(glycine)

41. Representation of the constitution of a protein

42. Three D representation of the structure of a protein

43. DNA 4

44. Thymine (T) The monomers: Adenine (A) Cytosine (C) Guanine (G)
Phosphate-
Sugar (backbone) of
DNA

45. Phosphate-sugar backbone holds the DNA macromolecule together

46. One strand unwinds to duplicate its complement via a polymerization of the monomers
C, G, A and T

47. Carbohydrates 4

49. Endless Possibilities
New Functional Groups
Different Polymer Backbones

50. Conclusions:
Polymers make up all sorts of materials that are all around us!
They can have a huge range or material properties based on their:
Functional Groups
Structure
Backbone
Keep thinking about how chemical interactions on the nano-scale correspond to material properties on the macro-scale

51. Links http://en.wikipedia.org/wiki/Plastic_recycling