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Polymers
Professor: Michael Eastman Ph.D.Assistant: David Chavez-Flores
Polymer
• Polymers are made up of many many molecules all strung together to form really long chains.
• Poly- means "many" and -mer means "part" or "segment".
Polymers: Introduction• Polymer: High molecular weight molecule made up of a small
repeat unit (monomer). – Homopolymer– A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A
• Monomer: Low molecular weight compound that can be connected together to give a polymer
• Oligomer: Short polymer chain• Copolymer: polymer made up of 2 or more monomers
– Random copolymer: A-B-B-A-A-B-A-B-A-B-B-B-A-A-B– Alternating copolymer: A-B-A-B-A-B-A-B-A-B-A-B-A-B– Block copolymer: A-A-A-A-A-A-A-A-B-B-B-B-B-B-B-B
Types of Polymers• Polymer Classifications
– Thermoset: cross-linked polymer that cannot be melted (tires, rubber bands)
– Thermoplastic: Meltable plastic– Elastomers: Polymers that stretch and then return to their original
form: often thermoset polymers– Thermoplastic elastomers: Elastic polymers that can be melted (soles
of tennis shoes)• Polymer Families
– Polyolefins: made from olefin (alkene) monomers– Polyesters, Amides, Urethanes, etc.: monomers linked by ester,
amide, urethane or other functional groups– Natural Polymers: Polysaccharides, DNA, proteins
Common PolyolefinsMonomer Polymer
EthyleneH3C
CH3
nRepeat unitPolyethylene
CH3
CH3n
CH3 CH3 CH3 CH3 CH3 CH3CH3Propylene
Polypropylene
PhCH3
n
Ph Ph Ph Ph Ph PhPhStyrene
Polystyrene
ClCH3
n
Cl Cl Cl Cl Cl ClClVinyl Chloride
Poly(vinyl chloride)
F2C CF2
Tetrafluoroethylene
F3C
F2C
CF2
F2C
CF2
F2C
CF2
F2C
CF2
F2C
CF2
F2C
CF2
CF3
nPoly(tetrafluoroethylene): Teflon
Polyesters, Amides, and UrethanesMonomer Polymer
CO2HHO2CHO
OHO O
HO OH2C
H2C O
nTerephthalic acid
Ethyleneglycol
Poly(ethylene terephthalateH
Ester
HO OH
O O
4H2N NH24
Adipic Acid 1,6-Diaminohexane Nylon 6,6HO N
HNH
H
O O
4 4n
CO2HHO2C
Terephthalic acid
NH2H2N
1,4-Diamino benzene
Kevlar
O
HO
OHN
HN H
n
Amide
HOOH
Ethyleneglycol
H2COCN NCO
4,4-diisocyantophenylmethaneSpandex
H2C
HN
HN
O
HO
O
OH2C
H2C O H
n
Urethane linkage
Natural PolymersMonomer Polymer
Isoprenen
Polyisoprene:Natural rubber
O
H
HO
H
HO
H
HOHH OH
OH
Poly(ß-D-glycoside):cellulose
O
H
O
H
HO
H
HOHH OH
OH
H
n
ß-D-glucose
H3N
O
O
RPolyamino acid:protein
H3N
OHN
R1
OHN
Rn+1
O
OH
Rn+2n
Amino Acid
BaseO
OH
OP
O
O
O
oligonucleic acidDNA
NucleotideBase = C, G, T, A
BaseO
O
OP
O
O
O
DNA
DNA
Making polyvinyl acetate
• Monomer - Vinyl Acetate
• Solvent - Water
• Initiator –Potassium Persulfate
H2CCH
O
CO
CH3H
O
H
O
S
O
O
S
O
O
O
K
KO
O
http://modules.utep.edu/Modules/polymer/Vinyl%20Acetate%20to%20PVAc/VA%20to%20PVAc.htm
Overall Reaction
H2CCH
O
CO
CH3
Water Heat
O
S
O
O
S
O
O
O
K
KO
O
n
O
S
O
OK
O
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3n
O
S
OO
K
O
Initiator
O
S
O
OK
O
H2CCH
O
CO
CH3
O
S
O
OK
O
H2C
CH
O
CO
CH3
H2CCH
O
CO
CH3
O
S
O
OK
O
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3
O
S
O
O
S
O
O
O
K
KO
OO
S
O
O
S
O
O
O
K
KO
OHeat
Bond brakes homolytically
Initiator
O
S
O
OK
O
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3
H2CCH
O
CO
CH3
O
S
O
OK
O
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3n
End of the reaction
O
S
O
OK
O
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3n
H2CCH
O
CO
CH3
O
S
OO
K
O
+
O
S
O
OK
O
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3
H2C
CH
O
CO
CH3n
H2C
CH
O
CO
CH3
O
S
OO
K
O
Procedure
• Place the exact amount of every reagent in a round bottom flask. http://modules.utep.edu/Modules/polymer/Vinyl%20Acetate%20to
%20PVAc/VA%20to%20PVAc.htm
– Vinyl Acetate 10 ml– Potassium Persulfate 0.1 g– Water 10 ml
Set Up
Water Inlet
Water Outlet
Source of Heat and Stirrer
Final Product
Nylon • Nylon is a generic designation for a family of synthetic polymers
known generically as polyamides and first produced on February 28, 1935 by Wallace Carothers at DuPont . Nylon is one of the most commonly used polymers
• Was used to replace Asian silk and hemp with nylon in parachutes in the World war II.
• Was also used to make tires, tents, ropes, ponchos, and other
military supplies
Nylon
Reaction Video Carleton Professor bob Burk from University, Ottawa, Canada
http://www.youtube.com/watch?v=y479OXBzCBQ
Demonstrations
• Making a rubber ball– http://modules.utep.edu/Modules/polymer/Rubber%20Balls/Rubber%20Balls.htm
• Diaper polymer• Teflon • Plastic bag • Carbon fiber video http://www.dailymotion.com/video/x4muy0_zoom-into-a-carbon-
fiber_tech
Science goals
• Produce more application-specific polymers • Produce biodegradable polymers• Dispose correctly of the polymers • Recycle the existing polymers
Bad disposal consequences
Questions• Is cotton a synthetic or natural polymer?
• What kind of polymer is the white glue?(a)Homopolymer(b)Alternating copolymer(c)Block copolymer (d)Random copolymer
• Besides of the monomer what else do you need to start a polymerization reaction?
(a) A radical(b) An atom(c) Water
