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Carbonyl addition-
elimination. III
BERKAY AKKOÇ
509161263
Polyamides
A polyamide is a polymer family that contains recurring amide
groups of: R-CO-NH-R’
as integral parts of the main polymer compound.
They are formed either by the polymerization of an amino
acid or the condensation of a polyamine with a
carboxylic acid in which the structural units are linked by
amide group bonding them together.
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
Polyamides
History
Nylon => Developed in the 1930’s at DuPont by Wallace
Carothers and his team of researchers.
Nylon is formed by the condensation reaction of two
components:
 Diamine (a compound containing two amino [NH2]
groups—e.g., hexamethylenediamine)
 Dicarboxylic acid (containing two carboxyl [CO−OH]
groups—e.g., adipic acid)
Or may be formed by the self-condensation of an amino acid
or an amino-acid derivative.
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
Nylon
Polyamides
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
Polyamides
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
Nylon 6
Polyamides
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
https://youtu.be/XIP8QwkCtX0
Nylon 6,6
Polyamides
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
Kevlar => In the early 1960s, DuPont was interested in
developing
“super fibers” due to the prior valuable invention of nylon,
 In 1965, research scientist Stephanie Kwolek from
DuPont discovered “kevlar”
Kevlar is formed by condensation reaction of two
components:
Para-phenylene diamine
Terephthaloyl (PPD-T) chloride
Kevlar
A B
Polyamides
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
Kevlar
https://youtu.be/CDfehw6LIR0?t=8
Polyamides
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
Nomex=> material developed in the early 1960s by DuPont
and first marketed in 1967
- An inherently flame-resistant, high-temperature fiber
- It is sold in both fiber and sheet forms and is used as a fabric
wherever resistance from heat and flame is required,
- Nomex is formed by condensation reaction of two
components:
Para-phenylene diamine
Terephthaloyl (PPD-T) chloride
Nomex
A B
Polyamides
 Introduction
 Nylon
 Chemistry
 Applications
 Kevlar
 Chemistry
 Applications
 Nomex
 Chemistry
 Applications
https://youtu.be/daoEWPvU1zU
Nomex
Polyesters
Polyester fibres are formed from synthetic polymers,
manufactured by the action of poly-functional acids with
poly-functional alcohols.
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Polyesters
Polyesters are extremely important polymers. Their most
familiar applications are in clothing, food packaging and
plastic water and carbonated soft drinks bottles.
The most used of the polyesters has the formula:
Being an ester, it is made from an acid, benzene-1,4-
dicarboxylic acid (terephthalic acid), and an alcohol, ethane-
1,2-diol.
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Polyesters
The different uses of polyesters depend on their structure.
The benzene rings in the molecular chain give them a rigid
structure, leading to high melting points (over 500 K) and
great strength.
They do not discolour in light.
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Polyesters
The polyester is produced as small granules. These are
melted and squeezed through fine holes and the resulting
filaments spun to form a fibre.
This fibre, commonly known as Terylene or Dacron, is widely
used in clothing (for example, in suits, shirts and skirts) either
alone or in blends with other manufactured or natural fibres,
principally cotton.
It is also used for filling anoraks and bedding duvets to give
good heat insulation. Other uses include car tyre cords,
conveyor belts and hoses, where its strength and resistance
to wear are paramount.
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Polyesters
The polyester can also be made into thin films which can be
used in:
food packaging, audio and video tapes, electrical insulation,
and X-ray films.
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Polyesters
A relatively newer use is for packaging, for example for
bottles (see Figure 3).
The small granules of the polyester are heated to about 500 K
and further polymerization takes place. This heating is
sometimes called solid-state polymerizing. The polymer is
melted, moulded and then stretched. The molecules are now
orientated in three directions giving the plastic great strength.
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Polyesters
Ethane-1,2-diol is reacted with benzene-1,4-dicarboxylic acid
(sometimes known as terephthalic acid), or its dimethyl ester,
in the presence of a catalyst, to produce initially the
monomer and low molecular mass oligomers (containing up
to about 5 monomer units).
Using the acid provides a direct esterification reaction, while
the dimethyl ester reaction involves ester interchange. The
dimethyl ester route requires the use of an acid catalyst
whereas direct esterification is self-catalysed by the
carboxylic acid groups.
The dimethyl ester route was originally preferred because the
ester could be purified more readily than the acid. Very pure
acid is now available in large commercial quantities; the
modern processes therefore start from the acid.
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Polyesters
The acid reacts directly with ethane-1,2-diol:
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Starting from the acid: Direct Esterification Reaction
Polyesters
The acid reacts with methanol to form the dimethyl ester,
with manganese(II) ethanoate being commonly used as the
catalyst.
The dimethyl ester is then reacted with ethane-1,2-diol, by a
process known as transesterification, in which one alcohol
(ethane-1,2-diol) exchanges for another (methanol)
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
(ii) Starting from the dimethyl ester: Ester Interchange Reaction
Polyesters
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
Granules of PET
Polyesters
The monomer then undergoes polycondensation with the
elimination of ethane-1,2-diol, a condensation reaction:
 Introduction
 Physical Properties
 Chemistry
 Uses of Polyesters
 As Fibres
 As Films
 As Packaging
 Manufacture of PET
 Production of monomer
 Polymerization of Polymer
https://youtu.be/qZ-yDF4Z5WA
Kim510 e carbonyl add elimination 3

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Kim510 e carbonyl add elimination 3

  • 2. Polyamides A polyamide is a polymer family that contains recurring amide groups of: R-CO-NH-R’ as integral parts of the main polymer compound. They are formed either by the polymerization of an amino acid or the condensation of a polyamine with a carboxylic acid in which the structural units are linked by amide group bonding them together.  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications
  • 3. Polyamides History Nylon => Developed in the 1930’s at DuPont by Wallace Carothers and his team of researchers. Nylon is formed by the condensation reaction of two components:  Diamine (a compound containing two amino [NH2] groups—e.g., hexamethylenediamine)  Dicarboxylic acid (containing two carboxyl [CO−OH] groups—e.g., adipic acid) Or may be formed by the self-condensation of an amino acid or an amino-acid derivative.  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications Nylon
  • 4. Polyamides  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications
  • 5. Polyamides  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications Nylon 6
  • 6. Polyamides  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications https://youtu.be/XIP8QwkCtX0 Nylon 6,6
  • 7. Polyamides  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications Kevlar => In the early 1960s, DuPont was interested in developing “super fibers” due to the prior valuable invention of nylon,  In 1965, research scientist Stephanie Kwolek from DuPont discovered “kevlar” Kevlar is formed by condensation reaction of two components: Para-phenylene diamine Terephthaloyl (PPD-T) chloride Kevlar A B
  • 8. Polyamides  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications Kevlar https://youtu.be/CDfehw6LIR0?t=8
  • 9. Polyamides  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications Nomex=> material developed in the early 1960s by DuPont and first marketed in 1967 - An inherently flame-resistant, high-temperature fiber - It is sold in both fiber and sheet forms and is used as a fabric wherever resistance from heat and flame is required, - Nomex is formed by condensation reaction of two components: Para-phenylene diamine Terephthaloyl (PPD-T) chloride Nomex A B
  • 10. Polyamides  Introduction  Nylon  Chemistry  Applications  Kevlar  Chemistry  Applications  Nomex  Chemistry  Applications https://youtu.be/daoEWPvU1zU Nomex
  • 11. Polyesters Polyester fibres are formed from synthetic polymers, manufactured by the action of poly-functional acids with poly-functional alcohols.  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer
  • 12. Polyesters Polyesters are extremely important polymers. Their most familiar applications are in clothing, food packaging and plastic water and carbonated soft drinks bottles. The most used of the polyesters has the formula: Being an ester, it is made from an acid, benzene-1,4- dicarboxylic acid (terephthalic acid), and an alcohol, ethane- 1,2-diol.  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer
  • 13. Polyesters The different uses of polyesters depend on their structure. The benzene rings in the molecular chain give them a rigid structure, leading to high melting points (over 500 K) and great strength. They do not discolour in light.  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer
  • 14. Polyesters The polyester is produced as small granules. These are melted and squeezed through fine holes and the resulting filaments spun to form a fibre. This fibre, commonly known as Terylene or Dacron, is widely used in clothing (for example, in suits, shirts and skirts) either alone or in blends with other manufactured or natural fibres, principally cotton. It is also used for filling anoraks and bedding duvets to give good heat insulation. Other uses include car tyre cords, conveyor belts and hoses, where its strength and resistance to wear are paramount.  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer
  • 15. Polyesters The polyester can also be made into thin films which can be used in: food packaging, audio and video tapes, electrical insulation, and X-ray films.  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer
  • 16. Polyesters A relatively newer use is for packaging, for example for bottles (see Figure 3). The small granules of the polyester are heated to about 500 K and further polymerization takes place. This heating is sometimes called solid-state polymerizing. The polymer is melted, moulded and then stretched. The molecules are now orientated in three directions giving the plastic great strength.  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer
  • 17. Polyesters Ethane-1,2-diol is reacted with benzene-1,4-dicarboxylic acid (sometimes known as terephthalic acid), or its dimethyl ester, in the presence of a catalyst, to produce initially the monomer and low molecular mass oligomers (containing up to about 5 monomer units). Using the acid provides a direct esterification reaction, while the dimethyl ester reaction involves ester interchange. The dimethyl ester route requires the use of an acid catalyst whereas direct esterification is self-catalysed by the carboxylic acid groups. The dimethyl ester route was originally preferred because the ester could be purified more readily than the acid. Very pure acid is now available in large commercial quantities; the modern processes therefore start from the acid.  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer
  • 18. Polyesters The acid reacts directly with ethane-1,2-diol:  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer Starting from the acid: Direct Esterification Reaction
  • 19. Polyesters The acid reacts with methanol to form the dimethyl ester, with manganese(II) ethanoate being commonly used as the catalyst. The dimethyl ester is then reacted with ethane-1,2-diol, by a process known as transesterification, in which one alcohol (ethane-1,2-diol) exchanges for another (methanol)  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer (ii) Starting from the dimethyl ester: Ester Interchange Reaction
  • 20. Polyesters  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer Granules of PET
  • 21. Polyesters The monomer then undergoes polycondensation with the elimination of ethane-1,2-diol, a condensation reaction:  Introduction  Physical Properties  Chemistry  Uses of Polyesters  As Fibres  As Films  As Packaging  Manufacture of PET  Production of monomer  Polymerization of Polymer https://youtu.be/qZ-yDF4Z5WA