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Polymer
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A long chain of molecules of the same type
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Individual molecule is called a monomer
Monomer
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Polymer
The chain of molecules is the polymer.
(poly – many)
Natural Polymers
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Cotton, silk, wool
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Natural rubber
a hydrocarbon
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Protein - essential ingredient in living matter
and is made up of monomers called amino
acids
Natural Polymer - Cellulose
Synthetic Polymers
(Plastics)
Product made
mostly from
petroleum petrochemical
Also consist of long
chains of
hydrocarbons
Example: polyethylene
Uses: garbage bags,
sandwich bags, food
containers
Petroleum
“black gold” “Texas tea”
1. Crude oil - form of petroleum important as an energy source
and use in making thousands of products.
2. Nonrenewable resource, which means that it cannot be
replaced once it is used up.
3. Separated into useful parts by a process called fractional
distillation and takes place in an oil refinery.
4. Some Products of petroleum:
Asphalt - Main material used for building roads.
Fuel - Burns easily and release large amounts of energy
Wax - Used in furniture polish and as a coating for milk
cartons
Plastics – from liquified petroleum gas
Polymerization
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Process of chemically bonding monomers to
form polymers
Synthetic polymers - rubber, plastic wrap,
and fabrics such as nylon, plastics
Plastics history
http://www.npr.org/templates/story/story.php?
storyId=114331762
Synthetic Rubber
Resin Identification Codes
#1 Polyethylene
The repeating monomer is C2H4, a hydrocarbon.
Containers for drinks, water,
ketchup & salad dressing,
peanut butter, pickles,
jelly/jams and edible oils.
• Ovenproof films and trays
• Carpet fiber
• Bottles
#2 High Density Polyethylene
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Milk, water, cosmetic,
shampoo, dish and
laundry detergents.
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Yogurt & margarine
tubs, cereal box
liners, grocery, trash
& retail shopping bags
Milk crates, totes,
recycle bins, 90 gal
garbage carts
How are these related?
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HDPE is also widely
used in the fireworks
community.. HDPE is
used as a replacement
for cardboard mortar
tubes for two primary
reasons.
1. safety, because the
tube will not shatter if it
explodes
2. The plastic tubes are
reuasable
And these?
#3 Polyvinyl chloride
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Polyvinyl chloride, PVC
Globally, over 50% of PVC manufactured is
used in construction.
Cheap and easy to assemble. PVC has been
replacing traditional building materials such as
wood, concrete and clay in many areas.
Concerns about effects on environment and
human health.
#4 LDPE & #5 Polypropylene
#4 LDPE Low Density Polyethylene
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Dry cleaner bags, bread and frozen food bags,
squeezable bottles like ketchup,
mustard, mayo and etc. Stretch wrap, shrink films
# 5 PP Polypropylene
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Ketchup bottles, yogurt and margarine tubs, medicine
bottles, VCR jackets,
carpet fiber and carpet backing, yarn carriers / cones,
tubes and spools
What is a CD case like?
#6 Polystyrene
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Colorless, hard plastic with limited flexibility. It
can be cast into molds with fine detail.
Can be transparent or can be made to take on
various colors
Economical
model assembly kits, plastic cutlery, CD "jewel"
cases, and many other objects
Styrofoam
What about “other?”
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# 7 plastic is usually a blend of different plastics
that have been recycled
Linear Polymers
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Microwaveable food containers, Dacron carpets.
To make a model of a linear polymer, connect some paper clips
together, end-to-end in a straight chain, like this:
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Each paper clip represents a monomer, and the chain of paper
clips is a model for a polymer.
In reality, the number of monomer units in a polymer commonly
ranges from 1,000 to 10,000 or more
Branched Polymers
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Soft, flexible shampoo bottles and milk jugs are
examples of products generally made using
branched polymers.
LDPE (low-density polyethylene)
Difficult to crosslink because of branches
Branched polymer
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When a sample of the polymer polyethylene is
magnified 15,000 times, you can see the
branch-like fibers.
Crosslinked Polymers
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Car tires and bowling balls are two examples of
products composed of cross-linked polymers.
HDPE
Properties
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Linear and Branched – thermoplastic
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More elastic
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More viscous
Crosslinked - thermoset
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Less elastic with more crosslinks
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More resistance to flow (less viscous)
What is Slime?
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This is a polymer made from white glue and sodium borate.
White glue is made with polyvinyl alcohol, or PVA, which is a
plastic made from oil. Borax is a natural mineral mined from the
earth, which is made of boron, sodium, oxygen, and water. It is
used as a laundry agent and cleaning product.
When you add water to glue, the PVA starts to dissolve in the
water. When you add the borax solution, it reacts with the PVA
to crosslink.
This crosslinking causes the gunk to undergo an irreversible
gel-like reaction and forms the substance we call Slime.
Slime Tests
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Description – How does your slime look like, feel, smell (waft), etc.?
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Slime Rating – Rate it from 1 = not very slimy to 5 = very slimy
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Slow Poke Test – Roll the slime into a ball and slowly poke your finger into the
slime. What happens? Does your finger go into the goop?
Quick Poke Test – Roll the slime into a ball and quickly poke the slime with your
finger. What happens? Does your finger go into the goop?
Slow Pull Test – Roll the slime into a ball and slowly pull on the ends.
What happens? Write your observations on your worksheet.
Quick Pull Test - Roll the slime into a ball and slowly pull on the ends.
What happens? Write your observations on your worksheet.
Blob Test – Grab a timer. Roll your slime into a ball and sit it on your plate or the
table. How long does it take for it to flatten out?
Hang Test - Grab a timer and a ruler. Roll your slime into a ball and hold it at a
height of 30 cm above the table. Time how long it takes for the goop to reach the
table.
Bounce Test - Roll your slime into a ball and drop from a height of 30 cm above the
table. What happens?
polymers intro.ppt
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http://lee.ifas.ufl.edu/FYN/FYNPubs/TheDanger
sofPlasticBags.pdf