MM Fibres- Their Properties

8/10/2019 MM Fibres- Their Properties

1/44


2/44


3/44


4/44

Wet Spinning

TvDical Wet SDun Fibers

Viscose

Acrilan

Creslan

Disadvantages

Slow 70 - 150 yddmin)

0 '

Washing to remove impurities

Solvent and chemical recovery

Advantages

Large tows can be handled

Man

Made

FibersAnd

Thek Propertla 3-3


5/44

Dry Spinning

TvDical

Dry

SRun Fibers

Acetate (acetone solvent)

Triacetate (methylene chloride)

Spandex (some) (dimethyl formamide)

Disadvantages

Flammable solvent hazards

0 ' Solvent recovery

Slow (?)

(200 - 400

yddmin)

Advantages

Yarn does not require purification

_ -

3-4 Man Made F i b e r s

And

Their

Properties


6/44

Melt Spinning

TvDical Melt Spun Fibers

Nylons

0 Polyester

Polypropylene

Disadvantages

Separate drawing step (unless spin draw)

Advantages

High speed

(275

to 1500 yddmin); (4000 yddmin spin draw)

Nosolvents

No purification problems


7/44

Extrusion

Of

Man Made Fibers

Spinning Methods)

A. W e t

Spinning Ravon)

B. Dry

Spinning

Polymer

Solution

--

Air

Outlet

Heating

Jacket

Winding

ilament

3-6 Man

Made

Fibers

And

Their Properties


8/44

C Melt SRinning

,- J

Hopper

=

Storage -

jp

Rollinish -.I

Filament

d f I

Winding

Man Made FlbersA n d Their Properties

3-7


9/44

Textile Fiber Parameters

Fibrous materials should possess certain properties for them to be

usekl

as

textile raw materials. Those properties which

are

essential

for acceptance

as a

suitable raw material may be classified

as

primary

properties , while

those

which add specific desirable

character

o r

aesthetics

to

the end product and

its use

may be classified as

secondary properties .

Prima-

ProDerties

Length; length-width ratio

Tenacity (strength)

Flexibility (pliability)

Acceptable extensibility for processing

Cohesion

Uniformity of properties

Secondary ProDerties

0

0

0

0

0

Physical shape (cross-section, surface contour, etc.

Specific gravity (influence weight, cover, etc.)

Moisture regain and moisture absorption (comfort, static

electricity, etc.)

Elastic character - tensile and compression

Thermoplasticity (softening point and heat-set character)

3-6 Man

Made

FibersAnd Thelr Properties


10/44

0 Dyeability

Resistance

to

solvents, corrosive chemicals, micro-organisms, and

environmental conditions

Flammability

Luster

Note: Cost is always a

factor

to consider

Man Made Aben A n d

Their Properties

3-9


11/44

Figure

3-

Typical Stress-Strain Curves

Of

Various Fibers

5 10 15 20

2 5 3 0

35

4 0 4 5 50

SMnPercent

3-10

Man

Made Fibers A n d Their

Properties


12/44

Key

Fiber

Properties Determined by Polymer

Composition And Structure

Melting Point

Modulus

Elasticity and recovery from strain

Tensile strength

Density

Moisture absorption

Dyeability

comfort

_-

Man

Made flben A n d Thelr

Propertles

3-11


13/44

>?

...

.... ,,.+ I.' =

...

.:.:..

........

::

.:.:.:.,.

...

-*-

Flat Oval, Lumen

Convolutions

Cotton

Cicular, Uniform in

diameter

Nylon, Dacron

Cuprammonium Rayon

Examples of Fiber Shapes

Y-Shaped

Celacbud

Acetate

Cumulofi Nylon

Type

20

Oval to round,

Overlapping scales

Medulla

Wool

Dog-Bone

Orlon, Verel,

Lycra

,y

...

Ribbon-Shaped

Dyne1

&&.

2'2EE=

........

Trilobal

Antron

Nylon

Triangular, Round

edges, Uniform

in

man-mades

Silk, Nylon

Type

90

Dacron

Type 62

Lobular

Lengthwise

Striations

Acetate

Circular, Serrated,

Lengthwise

Striations

Viscose Rayon

3-12 Man

Made FibersAnd Thelr roperties


14/44

Density and Specific Gravity'

Fiber Densits d c c )

Natural Fibers

Cotton

Flax

Silk

Wool

Man-made

Fibers

Acetate

Acrylic

Aramid

Flurocarbon

Glass

Modacrylic

Nylon

Nylon Qiana

Olefin

Polyester

Rayon

Spandex

1.52

1.52

1.25

1.32

1.32

1.17

-

1.18

1.38 1.44

2.2

2.49 - 2.73

1.30

-

1.37

1.14

1.03

0.91

1.22 or 1.38

1.50

-

1.52

1.20

-

1.22

*Ratio of weight of a given volume of fiber to an equal volume of water

_-

Man M a d e Fibers

A n d

Thelr Properties 3-13


15/44

Absorbency

Fiber Moisture Regain*

Natural Fibers

Cotton 7-11

Flax 12

Silk

11

Wool 13 - 18

Man-made Fibers

Acetate

Arne1 triacetate

Acrylic

&amid

Flurocarbon

Glass

Modacrylic

Nylon

Nylon Qiana

Olefin

Polyester

Rayon

Rayon

HWM

Spandex

6.0

3.2

1.3

-

2.5

4.5

0

0

- 0.3

0.4 - 4.0

4.0 - 4.5

2.5

0.01 - 0.1

0.4

-

0.8

15

11.5

-

13

0.75 - 1.3

*Moisture re ain

is

expressed as a percentage

of

the moisture-free

weight at 70 Farenheit and

65

relative humidity.

3-14 Man

Made

Rbers

A n d Their

Propertla


16/44

Heat And Textile Materials

Important Criter ia to Consider

Softening, melting, o r decomposition temperatures

Tendency of the fiber and fabric

to

shrink

when heat-relaxed, o r

stretch when heated and under tension

Ability

of

the fabric

t o

heat set

Ability of the fabric to h c t i o n properly at elevated temperatures in

one time

o r

repeated use

Ability of the fabric to ftnction properly at room temperature or

some other lower temperature) after exposure at

high

temperature

for

a

given period of time

_-

Man

Mode Fibers

A n d Thelr

Properties

3-15


17/44

Table 3- Thermal Properties

Fiber

k

atural Fben

I

Cotton

I Wool

Acetate

I Acrylic

I

Aramid

I

G la s s

Modacrylic

I Novoloid

I

Nylon6

I Nylon66

I

Olefin

I Polyester

PET

I Polyester

PCDT

~

-saran

;---

inyon

Spandex

Melting Point

Softening

Safe

Ironing

OF

O C

OF

OC

OF

O C

Sticking Point Temperature*

Nonmelting

425 2 18

Nonmelting

450 232

Nonmelting

300 149

Nonmelting

300 149

446

230 364

184 350

177

575

302 482

250 464

240

I

400-490

204-254 I 300-350 149-176

I

oes not melt, carbonizes above

800' F

1400-3033

200-250 93-12

1

Nonmelting

414

2 12 340

171 300

149

482

250 445

229 350

177

150

127

I lowest possible)

75 135

260

480 249 460 238 325 163

550 311 490 254 350 177

Nonmelting

375 19

350 177

300 149

Do not iron

446 230

347 175

300 149

285 140

200 93 Do not iron

-

3-16 Man

Made

FibersA n d

Their

PropeC.nes


18/44

Comparative Fiber Properties

-

Effect Of Acids

Acrylic

Modacrylic

Polyester

Rayon

Acetate

Triacetate

Nylon 66

Olefin

Glass

Cotton

Wool

Resistant t o most acids

Resistant to most acids

Resistant to most mineral ac

96%sulhric

is;

disintegrated by

Disintegrates in hot dilute and cold concentrated acids

Soluble in acetic acid, decomposed by strong acids

Similar to acetate

Decomposed by strong mineral acids, resistant

to

weak acids

Very resistant

Resists most acids. Etched by hydrofluoric acid and

hot phosphoric acid

Similar to rayon

Destroyed by hot sulfuric, otherwise unaffected

by acids

Man Made Rbers nd

Their

Properties

3-1

7


19/44

Comparative Fiber Properties Effects Of Alkalies

Acrylic

Modacrylic

Polyester

Rayon

Acetate

Triacetate

Nylon

66

Olefin

Glass

Cotton

Wool

Destroyed

by

strong alkalies at a boil, resists

weak alkalies

Resistant to alkalies

Resistant t o

cold

alkalies, slowly decomposed at a boil

by

strong alkalies

No effect by cold, weak alkalies, swells and loses

strength in concentrated alkalies

Saponified, little effect from cold weak alkalies

Not effected up to pH 9.8,205' F; better than acetate

Little o r no effect

Very resistant

Attacked by hot weak alkalies and concen-

trated alkalies

Swells when treated with caustic soda but is

not damaged

Attacked by weak alkalies, destroyed by

strong alkalies

3-18

ManMade

FibersA n d

The i r

Propetties


20/44

Comparative Fiber Properties Effect Of

Acrylic

Modacrylic

Polyester

Rayon

Acetate

Triacetate

Nylon 66

Olefin

Glass

Cotton

Wool

Organic Solvents

Unaffected

Soluble in warm acetone, otherwise unaffected

Soluble in some phenolic compounds, other-

wise unaffected

Unaffected

Soluble in acetone, dissolved or swollen by

many others

Soluble in acetone, chloroform and swollen

by

others

Generally unaffected, soluble in some

phenolic compounds

Soluble in chlorinated hydrocarbons above 160

Unaffected

Resistant

Generally resistant

Man

Made

Fibers

A n d Their

Properh

3-19


21/44

Comparative Fiber Properties - Effect Of Sunlight

Acrylic

Modacrylic

Polyester

Rayon

Acetate

Triacetate

Nylon

66

Olefin

Glass

Cotton

Wool

Little o r no effect

Highly resistant, some loss

of

strength and

discoloration

after

constant exposure

Some loss of strength, no discoloration, very resistant

behind glass

Generally resistant, loses strength after long exposure

Approximately same

as

rayon

Resistant, loses strength after long exposure

No

discoloration, strength loss after long exposure

Very resistant, retains 95 strength after 6

months exposure

None

Strength loss on long exposure

Strength loss, dyeing is affected

3-20 ManMade

Fibers

A n d Their Properties


22/44

Rayon

A Cellulosic Man-Made Fiber)

ComDosition

Regenerated cellulose

Physical ProDerties

0

0

0

0

0

0

0

Microscopic Appearance

- triations seen in viscose and high-strength rayon

-

f

delustered, scattered specks

of

pigment can be seen.

Length

-

ilament and staple

Color

- ransparent unless dulled by pigments

Luster

- igh unless delustering pigment added

Strength

-

air to

excellent

- egular rayon has fair strength

- igh tenacity types have good to excellent strength

Elasticity

-

egular rayon

is

low

- igh strength rayon is good

Resiliency

- igh wet-strength rayon is better

Man Made FibersA n d The ir roperties 3-21


23/44

Moisture Absorption

-

igher than natural cellulose

-

ibers swell in water

-

Weaker when

wet

Heat

-

oses strength above

300'

F

-

ecomposes between 350 and

400'

F

Flammability

-

urns rapidly unless treated

Electrical Conductivity

-

air - static charge can be reduced with special finishes

Specific Gravity

- .52 (similar

to

cotton)

Chemical ProDerties similar to cotton)

Easily damaged by strong acids

Resistant

t o

alkalies, reduction in strength

if

concentrated

Lengthy exposure

to

sunlight weakens the fabric

Greater

f i n i t y

for dyes than cotton

3-22 Man Made FibersAnd Their Properties


24/44

Acrylic

(A

Wool Like

Fiber)

ComD

osi

t

ion

Acrylonitrile and small amounts

of

other monomers

Physical Properties

Microscopic appearance

- niform and smooth surface

- rregular spaced striations

Length

* -Mainly a staple fiber

Color

-

White t o off-white

Luster

-

right, semidull,

or

dull

Strength

-

air t o

good strength

Elasticity

- ood

Resilience

- ood

Water Absorption

-1-3

Man

Made

f lbers

A n d Their Properties 3-23


25/44


26/44

Nylon

(A Polyamide Fiber)

Com osit ion

Nylon

66

-

Polyhexamethylene Adipamide

Nylon 6 - Caprolactam

Phvsical Proverties


- ery smooth and even

Length

,

-

ilament and staple

Color

- ff-white

Luster

- igh

natural

luster can be controlled

Strength

- xceptionally

high

(60,000 - 108,000)pounds per square inch

Elasticity

- xceptionally

high

Resiliency

- ery good

Moisture Absorption

-

.8

Man

Made

Fibers A n d Thelr Properties 3-25


27/44

~

0

0

0

0

Heat

igh resistance, melts at

482'

F

Flammability

-Melts slowly

- oes not support combustion


ow,

generates

sta t ic

Specific Gravity

- 1.14 low density)

Chemical ProDerties

Weakened by concentrated strong acids

High resistance to alkalies

Loses strength in prolonged exposure t o sunlight

-

bright yam more

resistant than dull yam

3-26 Man Made

Fibers

A n d

Their

Properties


28/44

Polyester

Most Versatile Fiber)

ComDosition

Combination

of

Terephthalic Acid

or

Dimethylterephthalate and

Ethylene Glycol

Phvsical ProDerties


-

mooth, even, rodlike, different cross-sectional shapes

Length

.

-

ilament and staple

Color

-White

Luster

-

right

or

dull

Strength

-

ood

t o

excellent

Elasticity

-

air t o good

- reater than cotton o r rayon

Resilience

-Excellent

-

Moisture Absorption

- ess than 1

Man

Mode

FibersA n d Thelr Properties 3-27


29/44

Heat

-

ofteningo r sticking temperature is above 400 F thermoplastic)

Flammability

u m slowly


-

ccumulates static changes

Specific Gravity

-

ypically 1.38

ChemicalPronerties

Good resistance t o most acids

Good

resistance to

most

alkalies

Good sunlight resistance

3-26

Man

Made Fibers

And Thelr

roperties


30/44

Figure

3-2

Production

of

Polyester

Drying

r - l

Drawing

FilamentYam

Staple Fiber

3

Drawing Tow

2

Crimping

3

Drying/Heat Setting

4 Cutting

Man Made

Fiben

A n d

Thelr

Propertles

3-29


31/44

Acetate

(A

Cellulosic Man-Made Fiber)

ComDosition

Acetate Ester

of

Cellulose

Phvsical ProDerties


-

triations farther apart than viscose rayon

-

obed cross-section

Length

-

ilament and staple

Color

-

ransparent unless dulled by pigments

Luster

-

right, semibright,

o r

dull

Strength

-

Moderate

-

ess than rayon when wet

Elasticity

-

ot

very

high

-

imilar

to

rayon

--

Resilience

- oor

3 30

Man

Made

Flbers

A n d Their roperties


32/44

Moisture Absorption

-

%,

little strength

loss

when wet

Heat

- roning temperatures of 275' F are satisfactory

Flammability

-

lowly combustible


-

ood

Specific Gravity

- .32

Chemical ProDerties

Concentrated strong acids will decompose it

Strong alkalies will damage

it

Long exposures

t o

sunlight produce a weakening effect

--

Man Made Fibers A n d Their Properties 3-31


33/44

Polypropylene

(An

Olefin Fiber)

ComDosition

Propylene

Physical ProDerties


-

mooth and rodlike

Length

-

ilament and staple

Color

-

ranslucent

Luster

-

ull, semidull, bright

Strength

- xcellent strength (depends on degree of polymerization)

Elasticity

- ood

Resilience

- ood resistance to crushing

0

Moisture Absorption

- one

3-32

Man

Made

A b e t s

A n d

Thek Properties


34/44

Heat

-

Melts a t about 330'

F

-

rogressive shrinkage can occur at

140'

F to

212'

F

Flammability

-

low burning


-

xcellent

Specific Gravity

* -

.90

to

0.91

Chemical ProDerties

Very resistant t o most acids

Very resistant t o alkalies

Dye pigments usually added

t o

the liquid before fibers are extruded

Loses strength

in

sunlight, degrades upon long exposure

Man Made RbenAnd Thelr Properties 3-33


35/44

Polyethylene

(An Olefin Fiber)

Compos t on

Ethylene

Phvsical ProDerties


-

mooth and rodlike

Length

- ilament and staple

Color

- ranslucent

Luster

-

ull, semidull, bright

Strength

-

air to

good (depends on degree

of

polymerization)

Elasticity

-

ood

Resilience

-

ood resistance to crushing

Moisture Absorption

-

one

3-34 Man Made Fibers

And

Their

Propertles


36/44

Heat

ery heat-sensitive

-Melts at about

260' F

Flammability

- low burning


-

xcellent

Specific Gravity

-

.90

to 0.91

Chemical

ProDerties

Very resistant

to

most acids

Very resistafit

to

alkalies

Dye pigments usually added

t o

the liquid before fibers are extruded

Loses strength in sunlight, degrades upon long exposure

_-

Man Made FibersAnd Their Properties

3-35


37/44

Moisture

Regain

(96)

Elongation Softening

( I

Melting

Point

( F)

7 - 8 3 - 7 NONE

otton

1.5

-

1.55

Acetate

1.32 6

(sM00-445'F

23

-

24 (m)500F

1.5 - 2.5 35 - 39 (sM20'F

crylic

1.16 - 1.18

NONE 3.1

-

5.3 I (s)135O-156O0

Nylon

66

Polyester

1.14

1.38

l.2 - 4.5

(sM5OF

(mM80-500'F

0.4 - 0.8

(sM5'F

(mM82'F

2-67

13

16

1

DNM

350400F

DNM

310-350'F

9 - 26 Decomposes

30

40

Decomposes

R.LIYOI1,

HT

1.50 1.53

Table 3-2 Textile Fiber Properties

Tenacity

(wet) (gpd)

Tenacity

(gpd)

specific

Gravity

3.0 - 4.9

3.3

-

6.4

I

1.3 - 1.5

1.2 - 1.4

2.0 - 3.6

1.6 - 2.9

Glass

9.6

-

19.9 6.7

-

19.9.50

-

2.55

F

~ ~~

3.0 - 7.2

~~

2.6 6.1

I

2.2 - 6.6 2.2 - 6.6

.0 - 5.7 1.9 - 4.3

Wool

1 1.5

.3

1

DNM

350-4509

- 5

251

3-36 Man

Made

Rbers

And

Thelr

PrOpertres


38/44

Summary Of Properties Desired

For

Textile Fibers

Azmarel and Domestic Reauirements

0

0

0

0

0

0

0

0

0

0

0

Tenacity: 3

-

5 gramddenier

Elongation at break: 10 35

Recovery from elongation:

100%

at strains up to 5

Modulus of elasticity:

30

-

60

gramddenier

Moisture absorbency:

2 5

Zero strength temperature (excessive creep and softening point):

above 215'

C

High abrasion resistance (varies with type fabric structure)

Dyeable

Low flammability

Insolublewt low swelling in water, in moderately strong acids

and bases and conventional organic solvents from room temperature

t o 100' c

Ease

of

care

Industrial Reauirements

Tenacity: 7 -

8

graddenier

Elongation

at

break:

8

-

15

Modulus of elasticity: 80 g radden ier

o r

more conditioned, 50

gr ad de ni er wet

Zero strength temperature: 250'

C

o r above

Man

Made FibersAnd Their Properties 3-37


39/44

Fiber

Property

Chart

Fiber Prover Is Due

To

Contn'buter

To

Fabric

ProDertv

Abrasion

Resistance

The ability of a fiber to

withstand the rubbing o r

abrasion i t gets in

everyday use

Tough outer layer, scales, Durability

or

skin

Fiber toughness Resistance to splitting

Flexible molecular chains

Abrasion resistance

Absorbency

or

Moisture Regain

The percentage of moisture

a bone-dry fiber Will absorb

from the a ir under

standard conditions of

.temperature

and

moisture

Hydroxyl groups

Amorphous areas

Aging Resistance

Chemical structure

Comfort, warmth, water

repellency, absorbency, static

Dyeability, spotting

Shrinkage

Wrinkle resistance

build-up

Storing of fabrics

ChemicalReactivity

The effect of acids, alkali,

oxidizing agents, solvents

Polar groups of molecules Care required in

cleaning/bleaching, ability to

take acid

o r

alkali finishes

Cohesiveness

The ability of fibers to cling

together during spinning,

not important

in

continuous filament

Crimp or twists Resistance to ravel

Cover

The ability to occupy

space for concealment

or protection

Crimp, curl, or twist

Cross-sectional shape

Warmth in fabric

Cost

-

less fiber needed

Creep

Delayed elasticity;

Recovers gradually

--&om strain

Lack of side chains, cross

links, strong bonds; in fabric

poor orientation

Streak dyeing and shiners


40/44

Density

see Specific Gravity

Dyeability

The fibers receptivity

to

coloration by dyes

Elastic Recovery

The ability of fibers to

recover from strain

Elasticity

The ability of a stretched

material to retum

immediately to

its

original size

Electric Conductivity

The ability to transfer

electrical charges

Elongation

The ability

to

be strztched,

extended, o r lengthened;

varies at different tempera-

tures and when wet or dry

Feltability

The ability of

fibers

to

mat together

Flammability

The ability to ignite

and burn

Amorphous areas and

dye sites

Molecular structure: side

chains, cross linkages,

strong bonds

Aesthetics and colorfastness

Processability of fabrics

Resiliency

Delayed elasticity or creep

Chemical structure: Poor conductivity causes

polar groups

fabric

to

cling to the body,

electric shocks

Fiber crimp

Increases tear strength

Molecular structure: mole- Reduces brittleness

cular crimp orientation Provides give

and stretchiness

Scale structure of wool

Chemical composition

Hand

The way

a

fiber feels: silky,

harsh, soft crisp, dry

Cross-sectional shape,

crimp, diameter, length

Heat Conductivity

away fiom the body

-- The ability to conduct heat

Crimp

Cross-sectional shape

Fabrics can be made directly

?om fibers

Special care required

during washing

Fabrics bum

Hand offabric

Warmth

Man ModeFibersA n d

Their

Properties 3-39


41/44

Heat Sensitivity

The ability to soften, melt, Heat vibrates molecules

or shrink when subjected Fewer intermolecular ironing temperatures

t o heat

forces and cross links

Determine safe washing and

Hydrophilic or

Hygroscopic

Bee Absorbency

Luster

The light reflected from Smoothness

a surface; more subdued Fiber length

than shine; light rays are

Flat

o r

lobal shape

broken up

Loft or Compressional

Resiliency

The ability to spring back

t o original thickness after Stiffness

being compressed

Fiber crimp

Luster

Luster Shine

Springiness, good cover

Resistance

to

flattening

Mildew Resistance Low absorption Care during storage

Moth Resistance Molecule has no sulfur Care during storage

Pilling

The bailing up of fiber

ends on the surface High molecular weight Unsightly appearance

of

fabrics

Pilling

iber strength

Specific Gravity and

Density

The measures of the weight

of a fiber; Density is the

weight in grams per cubic

centimeter and specific

gravity is the ratio of the

mass of the fiber

to

an

equal volume of water

at doc.

Molecular weight

Warmth without weight

Loftiness - full and light

Buoyancy t o fabric

3-40 Man

Made

FibersA n d

Their

roperties


42/44

StiffnessorRigidity

The opposite of flexibility;

the resistance

t o

bending

o r creasing

Strength

The ability

to

resist stress;

expressed as tensile

strength (pounds per

square inch)

or

as tenacity

(grams per denier)

Sunlight

Resistance

The ability

to

withstand

degradation from

direct sunlight

Toughness

Ratio of breaking stress

to

breaking strain

Body of fabric

Resistance to insertion of

yam twist

Molecular structure: Durability, tear strength,

orientation, crystallinity, sagging, pilling

degree of polymerization

Sheerer fabrics possible with

stronger fine

fibers

Chemical composition

Durability of curtains and

draperies, outdoor furniture,

outdoor carpeting

Outer surface of skin

of fiber deformation, gives

Resists rupture from

frictional resistance

Wicking

The ability of

a

fiber

to

transfer moisture along composition of

its surface outer surfaces

Chemical and physical

Makes fabrics comfortable

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Fiber Blends Some Reasons

For

Blending

To facilitate processing

To

improve properties

-

brasion resistance

- trength

- bsorbency

- dd

bulk

and warmth

-

and

- imensional stability

-

esistance to wrinkling

To produce multi-color fabrics

To reduce

cost

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MM Fibres- Their Properties

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Transcript of MM Fibres- Their Properties