Chapter 15 Acetate and
Triacetate Fibers
Introduction
? Fibers in which forming substance is
cellulose acetate where not less than 92%
of hydroxyl groups are acetylated,
replacing -OH groups with -COCH3.
? Acetate,2 of 3 -OH groups in each 6-
member ring are acetylated; ~2.5
? Triacetate,Nearly all -OH groups are
replaced 2.91~2.96
? Major use,lining fabrics for suits,coats,
draperies
Structures
? Surface,straited
? Cross-section,lobed
? Skin-core structure
? DP,250-300
? Much less H-bond than in rayon
Properties
? Acetate,hydrophilic,thermoplastic
? Triacetate,hydrophobic,higher
melting and softening temperature,
high crystallinity
? Wrinkle easily in hot water,dry
cleaning only
? Swells in water,mechanical
properties change in water
? Resist to weak alkali and acids
? Can be bleached
Properties
? Soluble in acetone
? Degrade in UV light
? Burns,melts,forms black beads with
vinegar like odder
Production
? Similar to cellulose rayon for the first
a few steps
? Cellulose mixed with acetic acid and
acetic anhydride,a sulfuric acid
catalyst is added
? acetylation takes place
? degradation of the polymer making
DP low
? triacetate is made first
? when water added,some acetyl
groups are removed
Grades for test 1
Chapter 16 Nylon Fibers
Introduction
? Nylon,man-made fibers in which fiber
forming substance is any long-chain
synthetic polyamide in which less than 85%
of the amide linkages are attached to 2
aromatic rings
? Invented in 1938 in Du Pont
? Largest market,carpet fiber 80% of market
? 14% industrial and consumer products,tire
cord,fabrics and ropes
? 11% apparel
Introduction
? Types,
? Mostly,Nylon 6 and Nylon 6,6
? Small amount,nylon 3,nylon 4,nylon 5,
nylon 7,nylon 8,nylon 12,nylon 4,6,
nylon 6,10
Structure
? Polymerization,condensation,eliminating a
H2O molecule
? Functional group,amide group
? Molecular configuration,linear zigzag
molecules forming well closely packed
pleated sheets
? IMF,H-bond
? Crystallinity,High 65~86%
? Cross-sectional and longitudinal shape,can
be any thing
Properties
? Tenacity,high due to high orientation and
crystallinity
? Elongation,high due to zigzag structure
? Recovery,high due to zigzag
? Energy of rupture,high due to high
tenacity and high elongation,one of the
toughest materials
? Flexibility,high due to zigzag
? Abrasion resistance,high
? Water absorption,highest among all
synthetic fibers
Properties
? Smooth round cross-section and uniformity
permit close packing
? Swells when absorbing moisture
? Static,not enough water absorption
? Low specific gravity,1.14g/cc
? Resilience,high,wrinkle free
? Can be laundered but not easy to clean
? Vulnerable to degradation in acids
? low resistance to sunlight
? melts and drips
Chapter 17 Polyester Fibers
Introduction
? Manufactured fibers in which fiber
forming substance is any long-chain
polymer composed of at least 85% by
weight of a substituted aromatic
carboxylic acid,including but not
restricted to substituted terephthalic
units
? Generic group members:
? PET (polyethylene terephthalate) ~95%
Introduction
? PCDT,poly(1,4-cyclohexylene
dimethylene),Eastman Kodak
? PEB,poly(ehtylene oxybenzoate),
produced in Japan,70’s and 80’s
Structure
? Smooth,even diameter
? diameter generally 12-25 mm
? white or off-white colors
? Intermolecular forces:
? dipole-dipole between benzene rings
? Linear polymer,DP 115-140
? Crystallinity,35%
? Orientation,very oriented
Properties
PET
? High tenacity due to high orientation
? High failure elongation
? Elastic recovery
? High with low stress,97% at 2% strain,
? Low with high stress because dipole-dipole
bonding is not strong enough to hold,leading to
intermolecular slippage
? Low compressional resilience,not good for
carpet fiber
Properties
? Very low moisture regain
? Low level of wicking due to hydrophobic
surface
? High electrical resistivity,static charge
likely at low humidity
? Medium specific gravity
? Pilling
? High dimensional stability
? High Tm 450~500 degree F
Properties
? Resistant to acids,potentially degrades in
concentrated alkalies
? No UV degradation
? Flammable with black smoke
? Melt drip
? Best thermal resistant among all general
use synthetics
Properties
PCDT
? Lower tenacity and elongation
? Superior elastic recovery
? Better compressional resilience,good for
end uses such as carpets,rugs,knitwear
and fiberfill
? Less pilling due to lower tenacity
Production
? Polymerization
? Form chips
? melt spinning
? drawing
? heat setting to increase crystallinity and
orientation,reduce elongation and
shrinkage
Modification
? High tenacity for tire cord (higher DP and
crystallinity)
? Wicking
? Sheath-core,polyester core,low melt
polymer sheath
? Du Pont Coolmax,20% more surface area
and maybe hydrophilic treated for wicking
? Dupont Thermax,hollow fibers,excellent
thermal insulation and 20% weight
reduction
Chapter 18 Olefin Fibers
Introduction
? Polypropylene and polyethylene or
copolymer of ethylene and propylene
? End uses:
? 52% used in carpets and rugs
? 4% interior textile products
? 43% industrial and consumer products
? 0.5% apparel
Polymerization
? Addition or chain growth
polymerization from ethylene or
propylene
Structures
? Intermolecular forces:
? Van der Waals
? Crystallinity,50-65%
? Composed of fibrils
Properties
? Tenacity,high
? linear molecules,easy to orient
? Elongation,medium but depends on
orientation
? Elastic recovery,high
? Abrasion resistance,high due to slick
surface or low surface energy
? Flammability,low due to melting
Properties
? Toughness (work of rupture),high
? Initial modulus,depends on
orientation,in general medium
? Moisture absorption,none
? Melting and glass transition
temperature
? PE Tm = 130° C,Tg = -120 ° C
? PP Tm = 170° C,Tg = -10 ° C
? Specific density,0.9 - 0.92
Chapter 19 Acrylic Fibers
Introduction
? Invented in conceptually in 1893
? Produced initially in 1944 and full
scale in 1950
? End uses:
? 75% in apparel
? 18% household
? 7% Industrial and consumer textiles
Polymerization
? Addition or chain growth
? Homopolymer,polyarylonitrile strong
but compact and highly oriented
? virtually impossible to dye
? Copolymers,other types of
monomers are included for a dyeable
fiber and easier to process,
? e.g,acrylic acid and vinylpyrrolidone
? most acrylic fibers are copolymers
Structure
? Microscopic
? cross-section,
? dog-bone shaped
? kidney-bean shaped
? round
? Longitudinal
? uniform diameter
? rod-like shape
Structure
? Molecular
? DP = 1000
? IMF,dipole-dipole interaction between
nitrile groups -C?N
? Crystallinity is not well-defined
Properties
? Mechanical properties similar to wool
but stronger
? Medium tenacity,better than wool
? Failure strain,medium
? High elastic recovery at low strain
level 90 - 95% at 1 % strain
? Moderate abrasion resistance
Properties
? Bulky,tend to crimp
? Wick but do not absorb water
? Low specific density,1.12 - 1.19
g/cm3
? Static electricity built up
Difference between three types
of yarns
? Ring spun yarn
? Rotor spun yarn
? Air-jet spun yarn
? What are the factors determining
yarn mechanical properties?
Review for test 2
? Structures of all the fibers covered so
far
? Properties of all the fibers covered so
far
? Why do the fibers perform differently
? Specific problems for different fibers
? Typical end uses for each fiber
? Yarn structure and property
relationship
Triacetate Fibers
Introduction
? Fibers in which forming substance is
cellulose acetate where not less than 92%
of hydroxyl groups are acetylated,
replacing -OH groups with -COCH3.
? Acetate,2 of 3 -OH groups in each 6-
member ring are acetylated; ~2.5
? Triacetate,Nearly all -OH groups are
replaced 2.91~2.96
? Major use,lining fabrics for suits,coats,
draperies
Structures
? Surface,straited
? Cross-section,lobed
? Skin-core structure
? DP,250-300
? Much less H-bond than in rayon
Properties
? Acetate,hydrophilic,thermoplastic
? Triacetate,hydrophobic,higher
melting and softening temperature,
high crystallinity
? Wrinkle easily in hot water,dry
cleaning only
? Swells in water,mechanical
properties change in water
? Resist to weak alkali and acids
? Can be bleached
Properties
? Soluble in acetone
? Degrade in UV light
? Burns,melts,forms black beads with
vinegar like odder
Production
? Similar to cellulose rayon for the first
a few steps
? Cellulose mixed with acetic acid and
acetic anhydride,a sulfuric acid
catalyst is added
? acetylation takes place
? degradation of the polymer making
DP low
? triacetate is made first
? when water added,some acetyl
groups are removed
Grades for test 1
Chapter 16 Nylon Fibers
Introduction
? Nylon,man-made fibers in which fiber
forming substance is any long-chain
synthetic polyamide in which less than 85%
of the amide linkages are attached to 2
aromatic rings
? Invented in 1938 in Du Pont
? Largest market,carpet fiber 80% of market
? 14% industrial and consumer products,tire
cord,fabrics and ropes
? 11% apparel
Introduction
? Types,
? Mostly,Nylon 6 and Nylon 6,6
? Small amount,nylon 3,nylon 4,nylon 5,
nylon 7,nylon 8,nylon 12,nylon 4,6,
nylon 6,10
Structure
? Polymerization,condensation,eliminating a
H2O molecule
? Functional group,amide group
? Molecular configuration,linear zigzag
molecules forming well closely packed
pleated sheets
? IMF,H-bond
? Crystallinity,High 65~86%
? Cross-sectional and longitudinal shape,can
be any thing
Properties
? Tenacity,high due to high orientation and
crystallinity
? Elongation,high due to zigzag structure
? Recovery,high due to zigzag
? Energy of rupture,high due to high
tenacity and high elongation,one of the
toughest materials
? Flexibility,high due to zigzag
? Abrasion resistance,high
? Water absorption,highest among all
synthetic fibers
Properties
? Smooth round cross-section and uniformity
permit close packing
? Swells when absorbing moisture
? Static,not enough water absorption
? Low specific gravity,1.14g/cc
? Resilience,high,wrinkle free
? Can be laundered but not easy to clean
? Vulnerable to degradation in acids
? low resistance to sunlight
? melts and drips
Chapter 17 Polyester Fibers
Introduction
? Manufactured fibers in which fiber
forming substance is any long-chain
polymer composed of at least 85% by
weight of a substituted aromatic
carboxylic acid,including but not
restricted to substituted terephthalic
units
? Generic group members:
? PET (polyethylene terephthalate) ~95%
Introduction
? PCDT,poly(1,4-cyclohexylene
dimethylene),Eastman Kodak
? PEB,poly(ehtylene oxybenzoate),
produced in Japan,70’s and 80’s
Structure
? Smooth,even diameter
? diameter generally 12-25 mm
? white or off-white colors
? Intermolecular forces:
? dipole-dipole between benzene rings
? Linear polymer,DP 115-140
? Crystallinity,35%
? Orientation,very oriented
Properties
PET
? High tenacity due to high orientation
? High failure elongation
? Elastic recovery
? High with low stress,97% at 2% strain,
? Low with high stress because dipole-dipole
bonding is not strong enough to hold,leading to
intermolecular slippage
? Low compressional resilience,not good for
carpet fiber
Properties
? Very low moisture regain
? Low level of wicking due to hydrophobic
surface
? High electrical resistivity,static charge
likely at low humidity
? Medium specific gravity
? Pilling
? High dimensional stability
? High Tm 450~500 degree F
Properties
? Resistant to acids,potentially degrades in
concentrated alkalies
? No UV degradation
? Flammable with black smoke
? Melt drip
? Best thermal resistant among all general
use synthetics
Properties
PCDT
? Lower tenacity and elongation
? Superior elastic recovery
? Better compressional resilience,good for
end uses such as carpets,rugs,knitwear
and fiberfill
? Less pilling due to lower tenacity
Production
? Polymerization
? Form chips
? melt spinning
? drawing
? heat setting to increase crystallinity and
orientation,reduce elongation and
shrinkage
Modification
? High tenacity for tire cord (higher DP and
crystallinity)
? Wicking
? Sheath-core,polyester core,low melt
polymer sheath
? Du Pont Coolmax,20% more surface area
and maybe hydrophilic treated for wicking
? Dupont Thermax,hollow fibers,excellent
thermal insulation and 20% weight
reduction
Chapter 18 Olefin Fibers
Introduction
? Polypropylene and polyethylene or
copolymer of ethylene and propylene
? End uses:
? 52% used in carpets and rugs
? 4% interior textile products
? 43% industrial and consumer products
? 0.5% apparel
Polymerization
? Addition or chain growth
polymerization from ethylene or
propylene
Structures
? Intermolecular forces:
? Van der Waals
? Crystallinity,50-65%
? Composed of fibrils
Properties
? Tenacity,high
? linear molecules,easy to orient
? Elongation,medium but depends on
orientation
? Elastic recovery,high
? Abrasion resistance,high due to slick
surface or low surface energy
? Flammability,low due to melting
Properties
? Toughness (work of rupture),high
? Initial modulus,depends on
orientation,in general medium
? Moisture absorption,none
? Melting and glass transition
temperature
? PE Tm = 130° C,Tg = -120 ° C
? PP Tm = 170° C,Tg = -10 ° C
? Specific density,0.9 - 0.92
Chapter 19 Acrylic Fibers
Introduction
? Invented in conceptually in 1893
? Produced initially in 1944 and full
scale in 1950
? End uses:
? 75% in apparel
? 18% household
? 7% Industrial and consumer textiles
Polymerization
? Addition or chain growth
? Homopolymer,polyarylonitrile strong
but compact and highly oriented
? virtually impossible to dye
? Copolymers,other types of
monomers are included for a dyeable
fiber and easier to process,
? e.g,acrylic acid and vinylpyrrolidone
? most acrylic fibers are copolymers
Structure
? Microscopic
? cross-section,
? dog-bone shaped
? kidney-bean shaped
? round
? Longitudinal
? uniform diameter
? rod-like shape
Structure
? Molecular
? DP = 1000
? IMF,dipole-dipole interaction between
nitrile groups -C?N
? Crystallinity is not well-defined
Properties
? Mechanical properties similar to wool
but stronger
? Medium tenacity,better than wool
? Failure strain,medium
? High elastic recovery at low strain
level 90 - 95% at 1 % strain
? Moderate abrasion resistance
Properties
? Bulky,tend to crimp
? Wick but do not absorb water
? Low specific density,1.12 - 1.19
g/cm3
? Static electricity built up
Difference between three types
of yarns
? Ring spun yarn
? Rotor spun yarn
? Air-jet spun yarn
? What are the factors determining
yarn mechanical properties?
Review for test 2
? Structures of all the fibers covered so
far
? Properties of all the fibers covered so
far
? Why do the fibers perform differently
? Specific problems for different fibers
? Typical end uses for each fiber
? Yarn structure and property
relationship
