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1. What is polymerization?
Polymerization is the process of chemically bonding monomers to form polymers.
Monomer Polymer
s
2. What are some examples of natural polymers?
Polypeptide
• Cotton, silk, wool, and natural rubber are all natural polymers Chain
made from plant or animal products.
• Protein is an essential ingredient in living matter and is made
up of monomers called amino acids. It is also called a
polypeptide chain.
• The DNA found in our cells is also a polymer. The monomer DNA
units of DNA are nucleotides and the polymer is known as a
polynucleotide.
Images: Top - http://bioinfo.bact.wisc.edu/themicrobialworld/lysozyme.gif Bottom: http://haplogroup-i.com/img/A4dna.jpg
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3. What are some examples of synthetic (manmade)
polymers?
• Some synthetic polymers are manmade rubber and fabrics
such as polyester, nylon, and rayon.
Safety Helmet
• Plastic is a synthetic polymer used to make a variety of
products, such as water bottles, plastic wrap, and kitchen
utensils as well as safety gear, computers, and rocket
engines.
• Polymers are also used in medicine as substitutes for
Nylon Rope
human tissues, such as bones and arteries.
4. What substances are used to make synthetic
polymers?
They are made from materials called petrochemicals, which Pins & screws used to
are made from petroleum Petroleum is made from the hold together bones
remains of plants and animals that have been buried beneath
sediments at the bottom of the ocean. Over time, heat and 3
pressure change the remains into petroleum, which is a
Polymers
Because the monomer units in synthetic polymers are
all the same (except for copolymers), an abbreviated
formula can be used.
Monomer Polymer
Ethylene polyethylene
H H
C C -(CH2-CH2 )-n
H H
Vinyl chloride poly(vinyl chloride)
H Cl
( 2-CH -)n
-CH
C C |
H H Cl
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Polymerization
Polymers are formed either by chain or stepwise
polymerization.
Chain polymerization ( Addition Polymerization):
A multi-step process involving initiation, propagation
and termination
Polymer size is relatively uniform
Ex- Polyethene
Stepwise polymerization
( Condensation Polymerization):
A process where polymer size and amount increase as a
function of time
Ex. Polyester 5
Polymer Types
Fibers result when the intermolecular forces between
polymer molecules are strong.
Chains can be lined up by stretching.
HO HO HO HO HO
O O O O
HO HO HO HO HO
O O O O
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Elastomers
In these polymers,
intermolecular
attractions are weak.
Cross-linking the chains
is one way of helping
them to maintain a
shape.
crosslink
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Plastics
Somewhere between fibrous polymers and elastomers.
Thermoplastic – soften when heated.
Example:
Polyethylene
Thermosetting plastic – do not soften when heated.
These are typically highly cross-linked polymers.
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Video Resources:
https://www.youtube.com/watch?v=LWxoDV-Ll8k&t=8s (Polymarisation)
https://www.youtube.com/watch?v=LWxoDV-Ll8k&t=8s ( Condensation poly
merisation)
https://www.youtube.com/watch?v=GhvevdJU_DM ( Addition polymer)
https://www.youtube.com/watch?v=HS0nMly6yt0 ( uses of polymers)
Resources:
https://courses.lumenlearning.com/introchem/chapter/types-of-synt
hetic-organic-polymers/
https://www.britannica.com/science/polymer
