A basic description of the Amide Link, Power point to introduce the making of Nylon 6,10

1. What is a polymer?
Dr. Robert D. Craig, Ph.D
Chemistry for Nursing
“The Amide Link”

2. AMIDES MENU
Background . . .
• An introduction to amides including their physical properties.
Preparation of amides . . .
• Their preparation from carboxylic acids, acyl chlorides and acid anhydrides.
The hydrolysis of amides . . .
• The hydrolysis of amides using acids or alkalis (including the test for an amide).
Other reactions of amides . . .
• The lack of base character in amides, the dehydration of amides to make nitriles, and
the Hofmann degradation of amides to make primary amines with one less carbon
atom.
Polyamides . . .
• A summary of the chemistry of simple polyamides like nylon and Kevlar, including
• their formation, structure, hydrolysis and uses.

3. What is a polymer?
• A polymer is a large molecule (
macromolecule) composed of repeating
structural units typically connected by
covalent chemical bonds.
• While polymers in popular usage suggests
plastic, the term actually refers to a large
class of natural and synthetic materials
with a wide variety of properties.

4. What is a polymer?
• Because of the extraordinary range of
properties accessible in polymeric
materials, they play an essential and
ubiquitous role in everyday life, ranging
from familiar synthetic plastics and
elastomers to natural biopolymers such as
DNA and proteins that are essential for
life.

5. Plastics
• Polyethylene:

6. DNA

7. Examples of polymers
• A simple example is polyethylene, whose
repeating unit is based on ethylene (IUPAC
name ethene) monomer. Most commonly, as in
this example, the continuously linked backbone
of a polymer used for the preparation of plastics
consists mainly of carbon atoms.
• .

8. Examples of polymers
• . The backbone of DNA is in fact based on
a phosphodiester bond, and repeating
units of polysaccharides (e.g. cellulose)
are joined together by glycosidic bonds via
oxygen atoms.

9. Examples of Polymers
• Styrofoam is a trademark of
Dow Chemical Company for closed-cell
extruded polystyrene foam currently made
for thermal insulation and craft
applications.
• In 1941, researchers in Dow's Chemical
Physics Lab found a way to make foamed
polystyrene

10. Styrofoam
• .

11. polystyrene
• The chemical makeup of polystyrene is a long
chain hydrocarbon with every other carbon
connected to a phenyl group (the name given to
the aromatic ring benzene, when bonded to
complex carbon substituents).
• Polystyrene's chemical formula is (C8H8)n; it
contains the chemical elements carbon and
hydrogen. Because it is an
aromatic hydrocarbon,

12. Kevlar

13. Kevlar has many applications!
• Kevlar has many applications, ranging from bicycle tires
and racing sails to body armor because of its high tensile
strength-to-weight ratio—famously: "...5 times stronger
than steel on an equal weight basis..."When used as a
woven material, it is suitable for mooring lines and other
underwater applications .

14. An artificial limb (prosthesis)
• An artificial limb is a type of prosthesis that
replaces a missing extremity, such as arms or
legs. Artificial limbs may be needed for a variety
of reasons where a body part is either missing
from the body or is too damaged to be repairedv

15. Who might be interested in artifical
limbs? The Military
• .

16. What are polyamides?
Polyamides are polymers where the
repeating units are held together by amide
links.
An amide group has the formula - CONH2.
An amide link has this structure:

17. Nylon
• In nylon, the repeating units contain
chains of carbon atoms. (That is different
from Kevlar, where the repeating units
contain benzene rings .) There are various
different types of nylon depending on the
nature of those chains.

18. Nylon-6,6
• Nylon-6,6 is made from two monomers each of which
contain 6 carbon atoms - hence its name.
• One of the monomers is a 6 carbon acid with a -COOH
group at each end - hexanedioic acid.

19. Nylon-6,6
• The other monomer is a 6 carbon chain
with an amino group, -NH2, at each end.
This is 1,6-diaminohexane (also known as
hexane-1,6-diamine).

20. condensation polymerisation.
• When these two compounds polymerise, the amine and
acid groups combine, each time with the loss of a
molecule of water. This is known as condensation
polymerisation.
• Condensation polymerisation is the formation of a
polymer involving the loss of a small molecule. In this
case, the molecule is water, but in other cases different
small molecules might be lost.

21. condensation polymerisation.
• The diagram shows the loss of water
between two of the monomers

22. condensation polymerisation

23. condensation polymerisatio
• This keeps on happening, and so you get
a chain which looks like this:

24. Kevlar
Kevlar is similar in structure to nylon-6,6 except
that instead of the amide links joining chains of
carbon atoms together, they join benzene rings.
• The two monomers are benzene-1,4-
dicarboxylic acid and 1,4-diaminobenzene

25. structure of Kevlar
• If you line these up and remove water
between the -COOH and -NH2 groups in
the same way as we did with nylon-6,6,
you get the structure of Kevlar:

26. POLYAMIDES
Begin structures, formation, hydrolysis and uses of the polyamides, nylon and
Kevlar.
What are polyamides?
Polyamides are polymers where the repeating units are held together by amide
links.
An amide group has the formula - CONH2. An amide link has this structure:
What are polyamides?
Polyamides are polymers where the repeating units are held together by amide links.
An amide group has the formula - CONH2
. An amide link has this structure:

27. National Institute of Standards
and Technology (NIST)
• Over the past couple of decades, atomic force
microscopy (AFM) has emerged as a powerful tool for
imaging surfaces at astonishing resolutions—fractions of
a nanometer in some cases. But suppose you're more
concerned with what lies below the surface?
Researchers at the National Institute of Standards and
Technology (NIST) have shown that under the right
circumstances, surface science instruments such as the
AFM can deliver valuable data about sub-surface
conditions.

28. electric force microscopy can be used to detail structures well below
the surface. Left, AFM height image showing the surface of a
polyimide/carbon nanotube composite. Right, EFM image revealing the
curved lines of subsurface nanotubes.
Credit: NIST

29. Institute for soldier nanotechnolgy
• The Institute for Soldier Nanotechnologies (ISN) at MIT
is an interdepartmental research center founded in 2002
by a $50 million, five-year contract with the U.S. Army
Research Office. Now in its second five-year contract,
the mission of the ISN is straightforward: develop and
exploit nanotechnology to dramatically improve the
survivability of Soldiers.
• The ultimate goal is to help the Army create a 21st
century battlesuit that combines high-tech capabilities
with light weight and comfort. Imagine a bullet-resistant
jumpsuit, no thicker than ordinary spandex, that monitors
health, eases injuries, communicates automatically, and
reacts instantly to chemical and biological agents. It’s a
long-range

30. AT MIT . . . . . . .
5 nanotechnology labs