Introduction to Polymers
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Transcript of Introduction to Polymers
Introduction to Polymers
Overview
• What are polymers?
• How are polymers named?
• What is a polymer crosslinker?
Polymers are all around us!
Contact lenses
Sport equipment Clothingpolyester
Plasticcontainers
Synthetic(man-made)
Natural
DNAWood
Carbohydrates(sugars)
Protein(amino acids)
Rubber
Toys
Polymer Definition
polymer
“many” “part”Polymers are large molecules made of
repeating parts
The repeating parts are chemical compounds
Polymers are made of chains of repeating compounds
Large(macro)
small(micro)
Polyester fibersPolyester coat
Polymers are made of chains of repeating compounds
Large(macro)
small(micro)
Polyester fibersPolyester coat
Strings of ‘ester’compounds
ester ester ester ester
Joined bycovalent bonds
Large(macro)
small(micro)
Polyester fibersPolyester coat
ester ester ester ester
Esters are compoundsmade of elements like
C, H, O
Covalent bonds form when these atoms
share electrons
Polymers are made of chains of repeating compounds
Naming polymers
ester ester ester ester Polyester
A A A A A A A PolyA
mer mer mer mer mer Polymer
sugar sugar sugar sugar
Name this polymer:
Naming polymers
ester ester ester ester Polyester
A A A A A A A PolyA
mer mer mer mer mer Polymer
sugar sugar sugar sugar
Name this polymer:Polysugar
(a carbohydrate!)
Crosslinkers stabilize polymer chains
ester ester ester ester
Polyester fibersPolymer molecule chains
A crosslinker is acompound that bonds polymer chains together
Beads on a string
One fiber
Crosslinkers stabilize polymer chains
ester ester ester ester
Polyester fibersPolymer molecule chains
Beads on a string
A crosslinker is acompound that bonds polymer chains together
One fiber
What are some properties of polymers?
How can we change the properties of polymers?
vs.
The chemical properties of repeat units and their crosslinkers determine the physical properties of polymers
• Density• Melting temperature
• Transparency• Stiffness
See-throughFlexible
Can’t see throughFlexible
Can’t see throughRigid, stiff
Remember the TP lab?How does TP absorb water?
cellulose cellulose cellulose
+ Water
Toilet paper contains a polymer called cellulose
Remember, paper comes from wood, a
natural polymer!
Example
Remember the TP lab?How does TP absorb water?
cellulose cellulose cellulose
cellulose cellulose cellulose
+ Water
Toilet paper contains a polymer called cellulose
Water loves cellulose!
This makes TP absorbant!
Example
Remember the TP lab?How does TP absorb water?
So, the chemical properties of a
polymer (cellulose) in paper help determine its physical properties
(absorbancy)
Example
Polyethylene (PE)
ethylene ethylene ethylene
An important synthetic polymer
Example
C CH H
H H
This is what the compound calledethylene looks like:
This repeating compound is called ethylene-Its chemical formula is C2H4
Polyethylene (PE)
ethylene ethylene ethylene
An important synthetic polymer
Example
C CH H
H HC CH H
H HC CH H
H HC CH H
H H
This is what the compound calledethylene looks like:
This repeating compound is called ethylene-Its chemical formula is C2H4
Polyethylene (PE)
ethylene ethylene ethylene
An important synthetic polymer
Example
Deoxyribonucleic acid(DNA)
An importantnatural polymer
Wow, that is complex!
Example
Deoxyribonucleic acid(DNA)
An importantnatural polymer
Wow, that is complex!
DNA double helix
Cartoon ofDNA
Example
polymer
Polymers are used in medical devices
hip
knee
Shin bone
Thigh bone
Thigh bone
cartilage
pelvis
Polymer Synthesis Lab!
Homemade silly putty
C CH H
H OH
Repeat unit = vinyl alcohol
Crosslinker = borate ionsBOH
OHOHHO
Homemade silly putty
C CH H
H O
B
C CH H
O HC CH H
H OC CH H
O H
B
C CH O
H HC CO H
H HC CH O
H HC CO H
H H