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