1. The Structure and Properties of Polymers
Also known as
Bonding +
Properties

2. What is a polymer?
A long molecule made up from lots of small molecules called
monomers.

3. Break it down…
Poly- Many
Mono- One
Meros- Part
“mer”
Macro- Many

4. Translate this…
“I’m Hermann Staudinger. I say that rubber has a polymeric structure.”

5. All the same monomer Monomers all same type (A) A + A + A + A 
eg poly(ethene) polychloroethene PVC

6. Different monomers Monomers of two different types A + B A + B + A + B
eg polyamides
polyesters

8. So what does a synthetic polymer look like?

9. Addition polymerisation
Monomers contain C=C bonds
Double bond opens to (link) bond to next monomer molecule
Chain forms when same basic unit is repeated over and over

10. Copolymerisation when more than one monomer is used.
An irregular chain structure will result eg propene/ethene/propene/propene/ethene
Why might polymers designers want to design a polymer in this way?

11. Bellringer: Acid Plant Observations!
Hwk: Finish Lab Template!
Hwk: Finish Lab Template!

13. Make Your Own Lab
Task: Design and Conduct (if time!) a lab that will examine “stress-strain behaviors of your “Original Recipe” polymer.
You will have tomorrow to conduct your experiment also
There are 3 types of “stress-strain” behaviors…

14. Stress-Strain Behaviors
Tensile Strength
Amount of pulling force placed on a material before it breaks
Abrasion Resistance
Toughness of material against scraping, scuffing, or scarring
Puncture Strength
Ability of a material to keep moving objects from perforating a surface.

15. Congrats to Billy on finishing 41st of 526 at the Turkey Trot 10K!
Test Next Tuesday!
Welcome Back!
Bellringer- Acid Plant Lab Observation (only one this week!)
Hwk- QUIA Monday 11/28 (already up!)
Congrats to Billy on finishing 41st of 526 at the Turkey Trot 10K!

16. Today 11/28/11 Observations Thanksgiving sweep!
Make sure you get your Recycling # Sheet!
Thanksgiving sweep!
Strengths/Types of Polymers

17. What decides the properties of a polymer?
3 Main Factors:
1.) Chain Length
-Longer chain = ____________
2.) Chain Branching
-More branching = ___________
3.) Interchain Bonding (CROSS LINKS!!!!)

18. These Factors influence…
Morphology
Form or structure

19. Crystalline and amorphous polymers
Both amorphous and crystalline areas can be in the same polymer.
Crystalline - regular chain structure - no bulky side groups.
Amorphous- disordered
More crystalline polymer = stronger and less flexible.

20. Thermoplastics (~85%) No cross links between chains.
Weak attractive forces between chains broken by warming. (erasers, gelatin)
Change shape - can be remoulded.
Weak forces reform in new shape when cold.

21. Gelatin…no cross-linking

22. PVC

24. Polyethylene terephthalate (like in disposable water bottles)

25. Sodium Polyacrylate – in diapers!

26. Polystyrene (styrofoam)

27. Teflon – nonstick coating on pans…also used to make Gor-Tex

28. Thermosets Extensive cross-linking formed by covalent bonds.
Bonds prevent chains moving relative to each other.
Best suited to high-temperature applications – can be brittle when very cold.

29. Examples of thermosets:
Epoxy resins
Vulcanized rubber (car tires)
Injected molded items like milk crates.

30. Rubber (below is a monomer)

31. Examples of amorphous polymers:polyproplene

32. Nylon