PROPERTIES & USESE OF TEXTILE FIBERs

WOOL

PHYSICAL PROPERTIES

1. Color: The color of wool fiber could be white, near white, brown and black.

2. Strength: Wool is the weakest of all natural textile fibers. Wool fabric is strengthened by the use of ply yarns. A hard-twisted two-ply yarn may be regarded as an assurance of durability. Tightly twisted single yarns also make a strong fabric.

3. Elasticity: The fiber may be stretched from 25 or 30 percent of its natural length before breaking. This characteristic reduces the danger of tearing under tension and contributes to free body movements. Wool fibers can be stretched up to 50% when wet and 30% when dry and still bounce back to their original shape when stress is released. To preserve this natural elasticity.

4. Specific Gravity: Specific gravity is 1.3-1.32

5. Moisture Regain: Standard moisture regain is 16-18%

6. Luster: Luster of course fiber is higher than fine fiber

7. Resilience: Wool fabrics resist wrinkles. Wool is the most resilient fiber because it has a natural crimp that helps it keep its shape.Wool is very soft and resilient; poor wool is harsh.

8. Drapability: Wool’s excellent draping quality is aided by its pliability, elasticity and resiliency. Drapability is one of the competitive features of wool fabrics over many man- made fibers.

9. Heat Conductivity: As wool fibers are non-conducts of heat, they permit the body to retain its normal temperature. Wool fabrics have built-in climate control. Wool is a natural insulator and keeps the body warm in winter and naturally breathable to keep the body cool in summer.

10. Cleanliness and Washability: The wool fabrics adheres dirt and requires to be thoroughly cleaned. Care should be taken while laundering as the fiber is softened by moisture and heat which results in shrinking and felting of the fabrics washed. Wool fabrics temporarily lose about 25 percent of their strength when wet. Thus wool fabrics should never be pulled or wrung while wet.

11. Shrinkage: The wool fabrics shrink when washed. The fabrics which are dry-cleaned shrink less.

12. Effect of Heat: Wool becomes harsh at 212°F (100°C) and begins to decompose at slightly higher temperatures. It will scorch at 400°F (204°C) and will eventually char. Wool fiber does not burn freely when touched by flame.

1. Absorbency: Wool fiber is the original wicking fiber. Initially, wool tends to be water- repellent. The water lies on the surface of the fabric, which can be readily brushed off. However, once the moisture seeps between the scales of the fiber, the fiber’s high degree of capillarity will result in ready absorption. Wool can easily absorb up to 30% of its weight in moisture without feeling damp or clammy. Wool also dries slowly.

2. Effect of Light: Wool is weakened by prolonged exposure to sunlight.

3. Resistance to Mildew: Moisture content is the main factor for the development of mildew on a fabric. Wool is not ordinarily susceptible to mildew as the fabric does not absorb moisture easily. However, when the fabric is left in a damp condition, mildew develops.

CHEMICAL PROPERTIES

1. Reaction to Alkalis: Wool is quickly damaged by strong alkalis, which make it essential to use a mild soap or detergent when laundering wool fabrics.

2. Reaction to Acids: Although wool is damaged by hot sulfuric acid, it is not affected by other acids, even when heated. This property permits wool to be carbonized without damage.

3. Affinity for Dyes: When wool fabrics are dyed, the dye reaches the core of the fiber and bonds permanently. Wool absorbs many different dyes deeply, uniformly and directly without the use of combining chemicals. Because of their high affinity for dyes, wool fabrics dye well and evenly.

4. Resistance to Perspiration: Wool is weakened by alkali perspiration. Woolen garments should be dry-cleaned or washed with care to avoid deterioration and odor. Perspiration generally will cause discoloration.

5. Reaction to Bleaches: The chlorine bleaches like sodium hypochlorite are harmful for the wool fabrics. They can be safely bleached with hydrogen per oxide or sodium per borate.

USES OF WOOL

Wool is a multifunctional fibre with a range of diameters that make it suitable for clothing, household fabrics and technical textiles.

Its ability to absorb and release moisture makes woollen garments comfortable as well as warm. Two thirds of wool is used in the manufacture of garments, including sweaters, dresses, coats, suits and "active sportswear". Blended with other natural or synthetic fibres, wool adds drape and crease resistance.

Slightly less than a third of wool goes into the manufacture of blankets anti-static and noise- absorbing carpets, and durable upholstery (wool's inherent resistance to flame and heat makes it one of the safest of all household textiles).

Industrial uses of wool include sheets of bonded coarse wool used for thermal and acoustic insulation in home construction, as well pads for soaking up oil spills.

Read more: http://textilelearner.blogspot.com/2011/08/characteristics-of-wool- fabrics_4217.html#ixzz43jqdUw2h

SILK

PHYSICAL PROPERTIES

1. Color: The color of silk fiber could be yellow, brown, green or grey

2. Strength: Silk as a fiber, has good tensile strength, which allows it to withstand great pulling pressure. Silk is the strongest natural fiber and has moderate abrasion resistance. The strength of the thrown yarns is mainly due to the continuous length of the fiber. Spun silk yarn though strong is weaker than thrown silk filament yarns.

3. Elasticity: Silk fiber is an elastic fiber and may be stretched from 1/7 to 1/5 of its original length before breaking. It tends to return to its original size but gradually loses little of its elasticity. This would mean that the fabric would be less sagging and less binding resulting in the wearers comfort.

4. Specific Gravity: Specific gravity is 1.25 - 1.34

5. Moisture Regain: Standard moisture regain is 11%

6. Luster: Bright

7. Resilience: Silk fabrics retain their shape and have moderate resistance to wrinkling. Fabrics that are made from short – staple spun silk have less resilience.

8. Drapability: Silk has a liability and suppleness that, aided by its elasticity and resilience, gives it excellent drapability.

9. Heat Conductivity: Silk is a protein fiber and is a non-conductor of heat similar to that of wool. This makes silk suitable for winter apparel.

10. Absorbency: Silk fabrics being protein in nature have good absorbency. Silk fiber can generally absorb about 11 percent of its weight in moisture, but the range varies from 10 percent to as much as 30 percent. This property is also a major factor in silk’s ability to be printed and dyed easily.

11. Cleanliness and Washability: Silk fabric does not attract dirt because of its smooth surface. The dirt, which gathers can be easily removed by washing or dry cleaning. It is often recommended for the silk garments to be dry-cleaned.

12. Shrinkage: Silk fabrics are subjected only to normal shrinkage which can be restored by ironing. Crepe effect fabrics shrink considerably in washing, but careful ironing with a moderately hot iron will restore the fabric to its original size.

13. Effect of Heat: Silk is sensitive to heat and begins to decompose at 330° F (165° C). The silk fabrics thus have to be ironed when damp.

14. Effect of Light: Silk fabric weakens on exposure to sun light. Raw silks are more resistant to light than degummed silk.

1. Resistance to Mildew: Silks will not mildew unless left for sometime in a damp state or under the extreme conditions of tropical dampness.

2. Resistance to Insects: Silk may be attacked by the larvae or clothe moths or carpet beetles.

CHEMICAL PROPERTIES

1. Reaction to Alkalis: Silk is not as sensitive as wool to alkalis, but it can be damaged if the concentration and the temperature are high. A mild soap or detergent in lukewarm water is thus advisable.

2. Reaction to Acids: Concentrated mineral acids will dissolve silk faster than wool. Organic acids do not harm silk.

3. Affinity for Dyes: Silk has good absorbency and thus has good affinity for dyes. Dyed silk is colorfast under most conditions, but its resistance to light is unsatisfactory.

4. Resistance to Perspiration: Perspiration and sunlight weakens and yellows silk fabrics. The silk itself deteriorates and the color is affected causing staining. Garments worn next to the skin should be washed or otherwise cleaned after each wearing.

5. Reaction to Bleaches: Silk, like wool, is deteriorated with chlorine bleaches like sodium hypochlorite. However, mild bleach of hydrogen peroxide or sodium per borate may be used for silk.

Uses of Silk:

Bulk of silk fibres produced is utilised in preparing silk clothes. Uses of pure silk are decreasing gradually due to its high cost value and costly maintenance. Production of synthetic fibres has posed a serious threat to the silk industry. Clothes in which Silk fibres are combined with other natural and synthetic fibres are in great demand not only in India but also in foreign countries. Seeing this demand many textile industries are manufacturing clothes like Teri-silk, cotsilk etc.

Besides silk being used as garments it is also used in other industries and for military purposes. It is used in the manufacture of fishing fibres, parachutes, cartridge bags, insulation coils for telephones and wireless receivers, tyres of racing cars, filter clothes for flour mills, and in medical dressings and suture materials. Insulation coils for telephones and wireless receivers, tyres of racing cars, filter clothes for flour mills, and in medical dressings and suture materials.

Read more: http://textilelearner.blogspot.com/2011/08/characteristics-of-silk- fabrics_5368.html#ixzz43kcB2RPW

COTTON

PHYSICAL PROPERTIES

1. Specific gravity: 1.52-1.55

2. Strength (Tenacity): 3.0 - 4.9 g/d (Cotton is 20% stronger when wet). Fiber elongation is almost linear to the stress imposed

3. Elasticity: Relatively low

4. Absorbency and MR%: 7-8% at standard conditions

5. Birefringence: 0.046

6. Dielectric constant: 3.9-7.5

7. Resistivity: Order of 109 ohm/cm3

8. Micronaire: 2.0 - 6.5 (upland cotton)

9. Denier: 0.7 - 2.3 (upland cotton)

10.Length: 0.9 - 1.2 in (upland cotton)

11. Diameter: 9.77 - 27.26µm

12. Coefficient of friction: 0.25 (for raw dry cotton, otherwise strongly changes for treated and/or wet fiber)

13. Breaking Extension: 5-7%

14. Resiliency: Relatively low

15. Dimensional Stability: Medium

16. Abrasion Resistance: Better

CHEMICAL PROPERTIES

17. Effect of Bleach: Cotton fiber is resistant to bleach & H2O2 , NaOCl , NaClO2 , Ca(OCl)Cl are used as bleaching agents.

18. Effect of Acid: Cotton fiber is dissolved in high concentrated mineral acid but organic acid cannot dissolve it.

19. Effect of Alkali: Cotton fiber is resistant to alkali. Scouring is done by using alkali for removing impurities.

20. Effect of Heat: Cotton fiber burns rapidly in air. It begins to turn yellow after several hours at 120oC and decomposes at 150oC.

1. Effect of Sunlight: Cotton fiber can absorb heat and energy from sunlight. But excess application of sunlight may degrade the polymer system of fiber as it is attacked by the UV- ray of sunlight.

2. Effect of Organic Solvent: Cotton fiber is well resistant to most organic solvent.

3. Dye ability: Reactive, Direct, Vat, Azoic, Mordant Dyes are used to dye cotton fiber. But the best dye for cotton fiber is Reactive Dye.

END USES OF COTTON:

Apparel - Wide range of wearing apparel: blouses, shirts, dresses, childrenswear, active wear, separates, swimwear, suits, jackets, skirts, pants, sweaters, hosiery, neckwear.

Home Fashion - curtains, draperies, bedspreads, comforters, throws, sheets, towels, table cloths, table mats, napkins

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NYLON

Physical Properties

1. Strength: Nylon has good tenacity and the strength is not lost with age. Nylon has a high strength to weight ratio. It is one of the lightest textile fibers is at the same time also one of the strongest. It is one of the fibers which are added at the points of wear such as knees and seats of jeans and toes and heels of socks. The strength of the nylon fabric is lost when wet. Nylon has excellent abrasion resistance.

2. Elasticity: Nylon has good elasticity which makes it much suitable for the apparel purposes. The excellent elasticity would mean that the nylon materials return to their original length and shreds the wrinkles or creases. Nylon like other fibers has its own limit of elasticity. If stretched too much, it will not completely recover its shape. The high elongation and excellent elastic recovery of nylon contributes to the outstanding performance in hosiery. Nylon hosiery recovers to its original shape at knees and ankles instead of bagging.

3. Moisture Regain: 3.5-5%

4. Luster: Bright to light

5. Resilience: Nylon fabrics have excellent resilience. Nylon fabrics retain their smooth appearance and the wrinkles from the usual daily activities can be removed easily.

6. Drapability: Fabrics of nylon filament yarn have excellent draping qualities. The drape of the fabrics made from nylon can be varied depending on the yarn size. The light weight sheer fabrics of nylon night gowns have high-draping quality. The medium-weight dress fabrics can drape very nicely.

7. Heat Conductivity: The heat conductivity of the nylon fabrics vary depending upon the fabric construction, the type of nylon (staple/filament) used in the construction etc. For instance, the filament nylon used in the open construction would be cooler when compared to the same filament used in a closed construction.

8. Absorbency: Nylon fabrics have low absorbency. The low absorbency of the fabrics tends to be advantageous and also disadvantageous. The main advantage of the nylons low absorbency is that the water remains on the surface of the fabrics and runs off the smooth fabric and hence dries quickly. This property makes the nylon fabrics suitable for raincoats and shower curtains. Nylon’s low absorbency has a disadvantage in that the fabric feels clammy and uncomfortable in warm, humid weather.

9. Cleanliness and Washability: Nylon fabrics are easy care garments. Nylon fabrics are smooth, non-absorbent and dry quickly. Dirt doesn’t cling to this smooth fiber, which can be washed easily or can be even cleaned by using a damp cloth.

10. Shrinkage: Nylon fabrics retain their shape and appearance after washing. It has good stability and does not shrink.

1. Effect of Heat: Nylon should always be ironed at low temperatures. Using hot iron will result in glazing and then melting of the fabric.

2. Effect of Light: Nylon fabrics have low resistance to sun light. They are not suitable for curtains or draperies as it is weakened by the exposure to sun light.

3. Resistance to Mildew: Nylon fabrics have absolute resistance to the development of mildew.

4. Resistance to Insects: Nylon is resistance to the moths and fungi.

Chemical Properties

5. Reaction to Alkalis: Nylon has excellent resistance to alkali's but the frequent and prolonged exposures to alkalis will weaken the nylon fabrics.

6. Reaction to Acids: Nylon is less resilient to the action of acids and is damaged by strong acids.

7. Affinity for Dyes: Nylon can be easily dyed with a wider range of dyes. The dyed fabrics retain their color and have good resistance to fading.

8. Resistance to Perspiration: Nylon fabrics are resistant to perspiration.

9. Effect of Bleaches: The nylon fabrics are white and generally do not require bleaching. The nylon fabrics which pick up color or develop graying should be bleached with oxidizing bleaches such as hydrogen peroxide.

Uses of Nylon

Apparel use: High tenacity nylons are used for parachute fabrics, cords and ropes. Having good dimensional stability, are used for ladies gloves, ladies hose, under wear, swimming wear, stocking, hosiery fabric etc.

Domestic use: It is used for home furnishing, in carpets, in upholstery and in ropes and cords.

Industrial use: In finishing nets, tire cords, filtering cloths, sewing threads, tow ropes are made of Nylon. It is used in manufacturing of belts of various machines (Flat belt, V-belts).

- See more at: http://textileapex.blogspot.com/2015/02/end-uses-properties-of- nylon.html#sthash.TWZ0eZgl.dpuf

Read more: http://textilelearner.blogspot.com/2011/08/characteristics-of-nylon- fabrics_745.html#ixzz43wDvNv6r

JUTE

Physical Properties

Length: The reeds of Jute fiber vary from 3 to 14 feet long, depending on the grade, and they show taper from root to end. Thick reeds contain coarse fiber and thin reeds contain finer fiber. It constitutes with ultimate fibers of average length of 2.5mm.

Fineness: It is a coarse fiber. Its diameter varies from 6 to 20 microns.

Strength: Fibers are not so strong when compared with some other bast fibers but have good tensile strength. Fibers are naturally hard and brittle and break off with abrasion. Resistance to mechanical wear is low and not durable especially on exposure in moisture reduces its strength. Its extension at break is 2%.

Color: The best quality fibers are pale white or silvery grey, common qualities are brownish and greenish are inferior, roots are usually darker without any luster. Better quality fibers shows matt and pitted surface with very poor strength.

Luster: Better quality fibers have fairly high luster but inferior quality fibers shows matt and pitted surface with very poor strength.

Roots: Base portion of the Jute stems is more rigid and has a stronger supporting bark than the rest of the stem. This is due to longer exposure of this part to the action of the sunlight and water. During grade shorting, the root portion are removed by cutting and baled separately known as bale cutting.

Cleanliness: Cleanliness of fiber is an essential factor for high grade. Adhering portions of bark, specks sticks etc. are undesirable which affects grading according to their degree of presence.

Chemicals Properties

Water: Jute is a hygroscopic fiber i.e. it takes in or gives out moisture to its surrounding atmosphere. Under standard testing atmosphere, moisture content value is 12.8% and moisture regain value of this fiber is 14.6%.

Acid: This fiber is damaged by the action of strong acid hence wet processing on Jute fiber is not done in acid medium.

Alkali: It is safe in alkali medium; hence wet treatment is done on alkali medium.

End use

Jute is used for making yarn, twine, rope, sacking, cloth, hessian cloth, carpet backing cloth, carpet, mat, wall cloth, shopping bag, and as packing materials.

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POLYESTER

Physical and Chemical Properties

Denier: 0.5 - 15

Tenacity : dry 3.5 - 7.0 : wet 3.5 - 7.0

%Elongation at break : dry 15 - 45 : wet 15 45

%Moisture Regain: 0.4

Shrinkage in Boiling Water: 0 - 3

Crimps per Inch: 12 -14%

Dry Heat Shrinkage: 5 - 8 (at 180 C for 20 min)

Specific Gravity: 1.36 - 1.41%

Elastic Recovery @2% =98 : @5% = 65

Glass Transition Temp: 80 degree C

Softening temp : 230 - 240 degree C

Melting point : 260 - 270 degree C

Effect of Sunlight : turns yellow, retains 70 - 80% tenacity at long exposure

Resistence to Weathering: good

Rot Resistence: high

Alkali Resistence: damaged by CON alkali

Acid Resistence: excellent

Organic Chemical Resistence: good

End Uses:

Apparel: blouses,shirts,carrer apparel, permanent press garments, suits, etc. Home furnishings, fire hoses,belting, ropes, tire cord,etc

Read more: http://textilelearner.blogspot.com/2011/07/polyester-fiber-pet-physical- properties_9005.html#ixzz43x2GfpSA

ACRYLIC

Physical Properties

Length: The length of the acrylic fiber can be controlled. That means, it may be in filament or staple form.

Fineness: Fineness of this fiber is also controllable. The filament yarns are made 75 to 200 denier ranges while staple fibers are made 2 and 3 denier cut into 1.5”, 2”, 3” and 4” length.

Strength and Extension: It is fairly strong fibre. Its tenacity is 5 gm per denier in dry state and 4.8 gm per denier in wet state. Extension at break is 15%. Good recovery from deformation.

Elasticity: It has an elastic recovery of 85% after 4% extension when the load is extremely released.

Cross-sectional shape: Normally round but cross-section of this fibre could be varied.

Appearance: It is about 30% bulkier than wool. Regarding insulating warmth, it has about 20% greater insulating power than wool.

Effect of heat and sunlight: This fiber has very good thermal stability. Safe ironing temperature is at 1600C. At 230 – 2350C acrylic sticks with the iron i.e. melting occurs. High temperature may sometime causes yellowing of this fiber.

Chemical Properties

Acid: It has good resistance to mineral acid.

Alkali: The resistance to weak alkali is fairly good but hot strong alkali damages this fiber.

Solvent: It has excellent resistance to common solvents, oils, greases, and natural salts.

Water: Moisture regain of this fiber varies from 1.5% to 3%. Easy to wash and quick drying.

Effect of Biological agents: This fiber is unaffected by mildew, moulds, larves and insects.

End use

100% acrylic is used mainly in sweater, jersey, knit outer wear fabric and blankets. It is used as a blend component with cotton, viscose, wool etc. It has good warmth and recovery property. It is also used for making carpet due to good resiliency property.

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