2. Content
Introduction
Caprolactam
Synthesis and production of Caprolactam
Polymerization process
Fiber formation
The average molecular weight
Chemical structure of nylon 6
Characteristics
End use
Content
Introduction
Caprolactam
Synthesis and production of Caprolactam
Polymerization process
Fiber formation
The average molecular weight
Chemical structure of nylon 6
Characteristics
End use
Content
Introduction
Caprolactam
Synthesis and production of Caprolactam
Polymerization process
Fiber formation
The average molecular weight
Chemical structure of nylon 6
Characteristics
End use
Content
Introduction
Caprolactam
Synthesis and production of Caprolactam
Polymerization process
Fiber formation
The average molecular weight
Chemical structure of nylon 6
Characteristics
End use
2
3. NYLON 6NYLON 6
Nylon 6 or polycaprolactam is a polymer developed by Paul Schlack at
IG Farben to reproduce the properties of nylon 6,6.
Nylon 6 is a family of polymers called linear polyamides.
Nylon-6 is made from a monomer called caprolactam.
It is formed by ring-opening polymerization.
It is a semi-crystalline polyamide.
Nylon is produced by melt spinning.
Available in staple, tow, monofilament, and multi-filament form.
It is sold under numerous trade names including Perlon, Dederon,
Nylatron, Capron, Ultramid, Akulon, Kapron and Durethan.
Introduction
Nylon 6 or polycaprolactam is a polymer developed by Paul Schlack at
IG Farben to reproduce the properties of nylon 6,6.
Nylon 6 is a family of polymers called linear polyamides.
Nylon-6 is made from a monomer called caprolactam.
It is formed by ring-opening polymerization.
It is a semi-crystalline polyamide.
Nylon is produced by melt spinning.
Available in staple, tow, monofilament, and multi-filament form.
It is sold under numerous trade names including Perlon, Dederon,
Nylatron, Capron, Ultramid, Akulon, Kapron and Durethan. 3
4. CaprolactamCaprolactam
Caprolactam is an organic compound with the formula (CH2)5C(O)NH.
This colourless solid is a lactam (a cyclic amide) of caproic acid.
Caprolactam is the precursor to Nylon 6, a widely used synthetic polymer.
Caprolactam was first described in the late 1800s when it was prepared by
the cyclization of ε-aminocaproic acid, the product of the hydrolysis of
caprolactam.
ε-Caprolactam: Crude oil → benzene → cyclohexane → cyclohexanone
→ cyclohexanone oxime → caprolactam
Caprolactam is an organic compound with the formula (CH2)5C(O)NH.
This colourless solid is a lactam (a cyclic amide) of caproic acid.
Caprolactam is the precursor to Nylon 6, a widely used synthetic polymer.
Caprolactam was first described in the late 1800s when it was prepared by
the cyclization of ε-aminocaproic acid, the product of the hydrolysis of
caprolactam.
ε-Caprolactam: Crude oil → benzene → cyclohexane → cyclohexanone
→ cyclohexanone oxime → caprolactam
Caprolactam is an organic compound with the formula (CH2)5C(O)NH.
This colourless solid is a lactam (a cyclic amide) of caproic acid.
Caprolactam is the precursor to Nylon 6, a widely used synthetic polymer.
Caprolactam was first described in the late 1800s when it was prepared by
the cyclization of ε-aminocaproic acid, the product of the hydrolysis of
caprolactam.
ε-Caprolactam: Crude oil → benzene → cyclohexane → cyclohexanone
→ cyclohexanone oxime → caprolactam
Caprolactam is an organic compound with the formula (CH2)5C(O)NH.
This colourless solid is a lactam (a cyclic amide) of caproic acid.
Caprolactam is the precursor to Nylon 6, a widely used synthetic polymer.
Caprolactam was first described in the late 1800s when it was prepared by
the cyclization of ε-aminocaproic acid, the product of the hydrolysis of
caprolactam.
ε-Caprolactam: Crude oil → benzene → cyclohexane → cyclohexanone
→ cyclohexanone oxime → caprolactam
Chemical structure of caprolactam
4
5. Synthesis and production of CaprolactamSynthesis and production of Caprolactam
Many methods have been developed for the production of caprolactam.
Most of the caprolactam is synthesised from cyclohexanone, which is
first converted to its oxime.
Treatment of this oxime with acid induces the Beckmann rearrangement
to give caprolactam:
Many methods have been developed for the production of caprolactam.
Most of the caprolactam is synthesised from cyclohexanone, which is
first converted to its oxime.
Treatment of this oxime with acid induces the Beckmann rearrangement
to give caprolactam:
Many methods have been developed for the production of caprolactam.
Most of the caprolactam is synthesised from cyclohexanone, which is
first converted to its oxime.
Treatment of this oxime with acid induces the Beckmann rearrangement
to give caprolactam:
The other methods involves formation of the oxime from cyclohexane
using nitrosyl chloride.
Cyclohexane is less expensive than cyclohexanone.
5
6. Polymerization ProcessPolymerization Process
Nylon 6 can be modified using comonomers or stabilizers during
polymerization to introduce new chain end or functional groups.
Nylon 6 is only made from one kind of monomer, a monomer called
caprolactam.
It is synthesized by ring-opening polymerization of caprolactam .
Caprolactam has 6 carbons, hence 'Nylon 6'.
Caprolactam is heated at about 533 °K in an inert atmosphere of
nitrogen for about 4-5 hours, the ring breaks and undergoes
polymerization.
Then the molten mass is passed through spinnerets to form fibres of
nylon 6.
Nylon 6 can be modified using comonomers or stabilizers during
polymerization to introduce new chain end or functional groups.
Nylon 6 is only made from one kind of monomer, a monomer called
caprolactam.
It is synthesized by ring-opening polymerization of caprolactam .
Caprolactam has 6 carbons, hence 'Nylon 6'.
Caprolactam is heated at about 533 °K in an inert atmosphere of
nitrogen for about 4-5 hours, the ring breaks and undergoes
polymerization.
Then the molten mass is passed through spinnerets to form fibres of
nylon 6. 6
7. Cont.Cont.
During polymerization, the amide bond within each caprolactam molecule
is broken.
With the active groups on each side re-forming two new bonds as the
monomer becomes part of the polymer backbone.
All nylon 6 amide bonds lie in the same direction.
Two ways to carry out a ring-opening polymerization of e-caprolactam.
Nylon 6 is made using a water-initiated process.
Nylon 6 is made using a strong base as an initiator.
Carried out in a semi batch reactor or a continuous tubular reactor (V K
Tube).
During polymerization, the amide bond within each caprolactam molecule
is broken.
With the active groups on each side re-forming two new bonds as the
monomer becomes part of the polymer backbone.
All nylon 6 amide bonds lie in the same direction.
Two ways to carry out a ring-opening polymerization of e-caprolactam.
Nylon 6 is made using a water-initiated process.
Nylon 6 is made using a strong base as an initiator.
Carried out in a semi batch reactor or a continuous tubular reactor (V K
Tube). 7
10. Average Molecular WeightAverage Molecular Weight
One of the most important factors in polymer processing is viscosity, which
is a function of molecular weight.
Since Polycaprolactam can be regarded at equilibrium as a
polycondensation polymer, the number-average molecular weight alone is
sufficient for its characterization.
The number-average molecular weight, of nylon 6 has been determined by
the methylation method.
The starting polymers were prepared from caprolactam and polymerized in
the presence of water in a glass capsule.
In a typical synthesis,5% water was employed and reacted for 4h at 240 ºC.
The reaction mass was ground to a particle size of 0.2-0.5 mm.
The lactam in the sample was extracted with boiling methanol.
One of the most important factors in polymer processing is viscosity, which
is a function of molecular weight.
Since Polycaprolactam can be regarded at equilibrium as a
polycondensation polymer, the number-average molecular weight alone is
sufficient for its characterization.
The number-average molecular weight, of nylon 6 has been determined by
the methylation method.
The starting polymers were prepared from caprolactam and polymerized in
the presence of water in a glass capsule.
In a typical synthesis,5% water was employed and reacted for 4h at 240 ºC.
The reaction mass was ground to a particle size of 0.2-0.5 mm.
The lactam in the sample was extracted with boiling methanol.
10
11. Cont.Cont.
Polycaprolactam suitable for fiber production has a molecular weight ranging from
14,000-20,000.
Molecular weight of repeat unit: 113.16 g/mol.
Molecular weights of nylon 6 are generally in the same range as those of nylon 6,6.
The melt viscosity of the polymer can be represented as a function of molecular
weight by the relationship:
In the case of nylons, the value of exponent a normally is in the range of 3.4-3.8.
MWav (polymer) = DP x MWav (mer)
Polycaprolactam suitable for fiber production has a molecular weight ranging from
14,000-20,000.
Molecular weight of repeat unit: 113.16 g/mol.
Molecular weights of nylon 6 are generally in the same range as those of nylon 6,6.
The melt viscosity of the polymer can be represented as a function of molecular
weight by the relationship:
In the case of nylons, the value of exponent a normally is in the range of 3.4-3.8.
η=K (Mw) a
11
12. Nylon 6 StructureNylon 6 Structure
o Extensive H-bonding between amide groups
o Vander walls forces between flexible methyl chains
o Tendency of hydrophobicity
o Extensive H-bonding between amide groups
o Vander walls forces between flexible methyl chains
o Tendency of hydrophobicity
o Extensive H-bonding between amide groups
o Vander walls forces between flexible methyl chains
o Tendency of hydrophobicity
o Extensive H-bonding between amide groups
o Vander walls forces between flexible methyl chains
o Tendency of hydrophobicity
Polymerization: ring opening polymerization
Functional group: amide group-(-CO-NH-)-
Molecular configuration: linear zigzag
Crystallinity: High
Cross-sectional and longitudinal shape: can be any thing
Polymerization: ring opening polymerization
Functional group: amide group-(-CO-NH-)-
Molecular configuration: linear zigzag
Crystallinity: High
Cross-sectional and longitudinal shape: can be any thing
12
14. The Main difference in between nylon 6 and nylon 6,6The Main difference in between nylon 6 and nylon 6,6
They have difference in polymer structure and physical properties.
Length of repeat unit and directionality
Polymerization mode
More favorable hydrogen bonding
• The arrangement of atoms for type 6,6 nylon allows for more favorable hydrogen
bonding than type 6 nylon.
More highly ordered
• Type 6,6 nylon is more crystalline and ordered than type 6 nylon
Higher melting point
• Type 6,6 nylon melts at 255-265°C, type 6 nylon melts at 210-220°C.
Lower permeability
• Type 6,6 nylon with its tighter, more dense, more ordered polymer structure retards
stain penetration due to lower permeability than type 6 nylon.
They have difference in polymer structure and physical properties.
Length of repeat unit and directionality
Polymerization mode
More favorable hydrogen bonding
• The arrangement of atoms for type 6,6 nylon allows for more favorable hydrogen
bonding than type 6 nylon.
More highly ordered
• Type 6,6 nylon is more crystalline and ordered than type 6 nylon
Higher melting point
• Type 6,6 nylon melts at 255-265°C, type 6 nylon melts at 210-220°C.
Lower permeability
• Type 6,6 nylon with its tighter, more dense, more ordered polymer structure retards
stain penetration due to lower permeability than type 6 nylon.
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15. Nylon 6 CharacteristicsNylon 6 Characteristics
Nylon 6 fibres are tough, possessing high tensile strength, as well as
elasticity and lustre.
They are wrinkle proof and highly resistant to abrasion and chemicals
such as acids and alkalis.
The fibres can absorb up to 2.4% of water, although this lowers tensile
strength.
The glass transition temperature of Nylon 6 is 47 °C.
As a synthetic fiber, Nylon 6 is generally white but can be dyed to in a
solution bath prior to production for different color results.
Its tenacity is between 6 and 8.5 gm/den with a density of 1.14 gm/cc.
Its melting point is at 215 °C and can protect heat up to 150 °C on average.
Nylon 6 fibres are tough, possessing high tensile strength, as well as
elasticity and lustre.
They are wrinkle proof and highly resistant to abrasion and chemicals
such as acids and alkalis.
The fibres can absorb up to 2.4% of water, although this lowers tensile
strength.
The glass transition temperature of Nylon 6 is 47 °C.
As a synthetic fiber, Nylon 6 is generally white but can be dyed to in a
solution bath prior to production for different color results.
Its tenacity is between 6 and 8.5 gm/den with a density of 1.14 gm/cc.
Its melting point is at 215 °C and can protect heat up to 150 °C on average.15
16. Nylon 6 CharacteristicsNylon 6 Characteristics
Tenacity: high
Elongation: high
Recovery: high
Energy of rupture: high due to high tenacity and high elongation
Flexibility: high
Resiliency: Excellent.
Dimensional stability: Good.
Specific gravity: 1.14g/cc
Softening point: nylon 6,6 – 2290C, nylon 6 – 1490C.
Easy to wash
Poor resistance to sunlight
Hand feel: Soft and smooth.
Melts instead of burning
Tenacity: high
Elongation: high
Recovery: high
Energy of rupture: high due to high tenacity and high elongation
Flexibility: high
Resiliency: Excellent.
Dimensional stability: Good.
Specific gravity: 1.14g/cc
Softening point: nylon 6,6 – 2290C, nylon 6 – 1490C.
Easy to wash
Poor resistance to sunlight
Hand feel: Soft and smooth.
Melts instead of burning
16
17. Some Major Nylon Fiber UsesSome Major Nylon Fiber Uses
Apparel: Blouses, dresses, foundation garments, hosiery, lingerie,
underwear, raincoats, ski apparel, windbreakers, swimwear, and
cycle wear
Home Furnishings: Bedspreads, carpets, curtains, upholstery
Industrial and Other Uses: Tire cord, hoses, conveyer and seat
belts, parachutes, racket strings, ropes and nets, sleeping bags,
tarpaulins, tents, thread, monofilament fishing line, dental floss
Apparel: Blouses, dresses, foundation garments, hosiery, lingerie,
underwear, raincoats, ski apparel, windbreakers, swimwear, and
cycle wear
Home Furnishings: Bedspreads, carpets, curtains, upholstery
Industrial and Other Uses: Tire cord, hoses, conveyer and seat
belts, parachutes, racket strings, ropes and nets, sleeping bags,
tarpaulins, tents, thread, monofilament fishing line, dental floss
17
18. Thank You For Your Attention!!Thank You For Your Attention!!
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