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Group members:Katie Chan (3)
Odilia Chan (4)Hilary Chang (5)Rachel Chen (6)
Charlotte Lee (18)
• condensation polyamide• Two type of nylon – Nylon 6,6 and Nylon 6• Formed by reacting equal parts of a diamine and
a dicarboxylic acid• Peptide bonds form at both ends of each
monomer
• Polymer chain of Nylon:
C
O
N
H
Polar functional group
dicarboxylic acid
diamine
(Hexane-1,6-dicarboxylic acid)
(1,6-diaminohexane)
The first approach: combining molecules with an acid (COOH) group on each end are reacted with two chemicals that contain amine (NH2) groups on each end.
Nylon 6,6, is made of hexamethylene diamine with six carbon atoms and adipic acid.
The second approach: a compound has an acid at one end and an amine at the other and is polymerized to form a chain with repeating units of (-NH-[CH2]n-CO-)x.
In this equation, if n=5, then nylon 6 is the assigned name.
Tires Tents Ropes used in the production of a high-grade
paper for U.S. currency Musical strings Fabrics
Collar part of the watch
Elasticity and rigidityThermoplasticHigh Density and Bulk propertiesHigh crystallinity
∵ amorphous regions contribute elasticity below melting temperatures
amorphous regions alternate with regions which are lamellar crystals
crystalline regions contribute strength and rigidity
• a thermoplastic (softens and flows on repeated heating and hardens when cooled)
• melting point of 536K • extruded into fibers above this
temperature ∵ held together by hydrogen bonds• chains slide over each other
• 1.15g/cm3• are light-weighted and are very fine ∵ shorter distances between the
amide groups
• above their melting temperatures• amorphous solids or viscous fluids chains approximate random coils
cause the bulky property.
∵ Planar amide (-CO-NH-) groups are very polar
forms multiple hydrogen bonds among adjacent strands
Nylon backbone is so regular and symmetrical
Hydrogen bonds exist between amide groups of nylon polymer chains
However…orientation of the –C=O and the –N-H groups :
1. on opposite sides (Fig. a)
Fig. a) the –C=O and the –N-H groups on opposite sides(trans-), making the chain straight
2. on the same side (Fig. b) polymer chain would be bent number of H-bonds formed between adjacent
chains would be lessC
O
NH
Fig. b) the –C=O and the –N-H groups on same sides(cis-), making the chain bent
• Dacron, also known as polyethylene terphthalate, or PET
• condensation polyester• Monomer: bis-ß-hydroxyterephthalate• Synthesized by the esterification of
terphthalic acid and ethylene glycol
• Synthesized from carboxylic acids & alcohol
• The functional groups include ether & ketone
ether Ketone
• Garment industry• Medical industry• Stationeries• Electronic industry• Others
Flat cloth
Socks
Silk thread
Gloves
Dacron polyester capacitors
Pressure sensitive adhesive tapes
Magnetic tapes…
• plastic bottles made from PET widely used for soft drinks
• flexible food packaging• Plastic food tray• Space blanket• Carrier for magnetic tape
Negative impacts:Plastics in general: Durable& degrade very slowly: • Molecular bonds• Make plastic so durable • Equally resistance to natural processes of
degradation Burning plastic -- release toxic fumes:• Manufacturing • Creates large quantities of chemical pollutantsBut• Thermoplastics can be remelted and reused•Thermoset plastics can be grounded up and make as filler
Nylon:• * Nylon oligomers– by product from nylon-6 factory
that increases industrial wasteAND 1)Degradable• Various synthetic polyamides degraded by
microorganisms
2) Toxic substances are produced • Break down in fire • Hazardous smoke, and toxic fumes or ash containing
Hydrogen Cyanide
3)High cost of disposal• Incinerating nylons• Recover the high energy used to create them• Most reach the garbage dumps, decaying very slowly 4) Cost of plastics rises • Rising dramatically
Major cause • Sharply rising cost of petroleum• →cost of raw material• Future oil reserves are uncertain
Positive impacts:• Plastics in general: 1)Widely used in different aspects∵ special
properties e.g. plastic containers, insulators, advertising
sign box.
2)Replacing natural materials e.g. cotton
• Nylon: 1) Insulators of electricity 2) High tensile strength ∵ presence of hydrogen
bond 3) High melting and Boiling point ∵ intermolecular
hydrogen bonds are hold between different chains
• http://www.encyclopedia.com/html/D/Dacron.asp
• http://www.infoplease.com/ce6/society/A0814472.html
• http://en.wikipedia.org/wiki/Dacron• http://www.uwplatt.edu/~sundin/114/
l114_39.htm• http://www.cem.msu.edu/~reusch/
VirtTxtJml/polymers.htm• http://en.wikipedia.org/wiki/Nylon• http://matse1.mse.uiuc.edu/polymers/
c.html• http://www.chemguide.co.uk/
organicprops/amides/polyamides.html• http://www.uwplatt.edu