The document discusses nylon 6 fiber, including its production from caprolactam. Caprolactam is produced from cyclohexanone through several chemical reactions. Nylon 6 is synthesized through ring-opening polymerization of caprolactam. The polymerization occurs at high temperatures and results in a semi-crystalline structure. Nylon 6 fibers are produced through melt spinning and have properties derived from hydrogen bonding between amide groups and van der Waals forces between flexible chains.

1. NYLON 6 FIBER
By: Asaye Dessie
Jan. 2019
NYLON 6 FIBER
By: Asaye Dessie
Jan. 2019
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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
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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
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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.
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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

8. Cont.…Cont.…
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9. Fiber ProductionFiber Production
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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.
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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
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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
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13. Cont..
Round & rod like with smooth surface and no striations
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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
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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
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18. Thank You For Your Attention!!Thank You For Your Attention!!
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