Monday, October 13, 2014

AN INTRODUCTION TO TEXTILE FIBRE

Cotton:
Cotton claims a 36-percent share of the textile fibers market. The fiber is prized for its comfortable, soft, breathable, absorbent qualities, which make it the fiber of choice for numerous apparel articles and a range of other textile products. With recent developments of various technical treatments, it also is finding its way into performance markets, such as athletic and outdoor apparel, that traditionally that have been dominated by man-made fibers. Worldwide, cotton is grown on 2.5 percent of the cultivated agricultural land and uses 3 percent of the water required for agricultural production.
Biotechnology plays a major role in giving the plants characteristics that helps to reduce their vulnerability to pests and increase productivity and chemical pesticides and herbicides are used to protect the crops. Organic cotton producers, by contrast, plant non-genetically modified seeds and practice methods such as crop rotation; soil fortification through the addition of organic matter.
Properties of cotton fibres considered by cotton spinners:Fibre fineness- It influences spinning limit, yarn strength, yarn evenness, yarn fullness, drape etc. Micronaire value (microgram per inch)of fibre is use to measure the fineness scale of cotton fibre. Micronaire value lies between 3.3-4.9.

Fibre length: It influences the spinning limit, yarn strength, yarn evenness, handle of product, luster of product, yarn hairiness and productivity. Staple length of cotton fibre is 26-32mm.

Fibre maturity: It influences loss of yarn strength, neppiness, a high proportion of short fibre, varying dyeability and processing difficulties.

Fibre strength: Very weak cotton tend to rupture during processing, since binding of the fibres into the yarn is achieved mainly by twisting and thus can exploit at most 30-70% of the strength of the material. Breaking strength of cotton fibre is 15-40 cN/ tex.
Why strength of wet cotton fiber is greater than dry cotton fiber?Answer: Cotton is a crystalline fibre. It has more than 60% crystalline region and the rest are amorphous region. Also there are many hydrogen bond that made it strong. When cotton is wetted amorphous portion of cotton temporary arranges a structure that can create 5% more hydrogen bond. This hydrogen bond increase the strength of wet cotton.

Viscose :Rayon is a manufactured regenerated cellulose fiber. Because it is produced from naturally occurring polymers, it is neither a truly synthetic fiber nor a natural fiber; it is a semi-synthetic or artificial fiber. Rayon is known by the name “Viscose rayon” and “artificial silk” in the textile industry. It usually has a high luster quality giving it a bright sheen.
Rayon was the first manufactured fibre. The term rayon was officially adopted by the textile industry. Like most manmade fibres rayon is not synthetic. It is made from wood pulp, a naturally – occurring, cellulose based material. As a result rayon properties are most similar to those of natural cellulosic fibres. Such as cotton or linen, than those of thermoplastic ,petroleum based synthetic fibres such as nylon or polyester.
Generally Eucalyptus trees is used as a raw material for manufacturing rayon.
Here I want to clear some perplexing point regarding viscose rayon fibre.

01. Rayon is the generic name of this Regenerated Cellulose fibre.

02. The U. S. Trade Commission defines rayon as "manmade textile fibers and filaments composed of regenerated cellulose".

03. Viscose is just one of the manufacturing process of preparing rayon & rayon produced form viscose process is called viscose rayon.

04. The process of making viscose rayon (viscose process) was discovered by English chemist Charles Frederick Cross and his collaborators Edward John Bevan and Clayton beadle in 1891. In 1904 the British rights of the viscose process were purchased by Courtaulds Ltd. who developed it into the most successful method of rayon in the world. Courtaulds Ltd. produced the first commercial viscose rayon in 1905

Different Method of Manufacturing Rayon:
Rayon's versatility is the result of the fiber being chemically and structurally engineered by making use of the properties of cellulose from which it is made. However, it is somewhat difficult to control uniformity between batches and it also requires high labor involvement. The continuous process is the main method for producing rayon. Different methods of production lead to distinctly different rayon fibers.

01. Nitrocellulose

02. Acetate method

03. Cuprammonium method

04. Viscose method

Of the methods mentioned, the viscose method is relatively inexpensive.

Modification of Viscose Rayon:

01. Cross-sectional Modification

02. Bubble-filled Filaments:

03. Spun-dyed Filament & Staple

04. Crimp

05. Surface Modified Yarn

06. High Tenacity Rayon:

07. High wet Modulus Rayons

08. Modal Fibre

09. Polynosic Rayon:

10. Tencel Rayon

One of viscose strengths is its versatility and ability to bend easily with many fibres. Sometimes to reduce cost other times for luster , softness or absorbency and resulting comfort.

Polyester:
Introduction: Polyester is a polymer with ester functional group as a main chain. This is also known by other name Terylene. It is available in many forms but commonly it is used as PET (polyethylene terephthalate).Other forms which are known are polycarbonate and plant cuticles or cutin. Polyesters are easily flammables on high temperatures. Due to its wrinkle resistance capacity it is widely spun together with other natural fibres. Liquid crystalline polymers have high heat resistance capacity so it is used in jet engines as an abradable seal. Its one wide spread application in the medical field is for making of heart valves. Some properties of Polyester are given below:

Properties:
• Wrinkle resistance

• Heat resistance

• Good mechanical properties

• Polymerization and cross linking is possible

• Thixotropic properties

• Azeotrophe esterification is possible

• Alcoholic transesterification is possible

• Thermoplastic qualities

• Combustible at high temperatures

• Thermosetting property

• Cross linking and polymerization is possible through exothermic reactions

Application of Polyester:

• Widely used in apparels

• Fiberfill is used in cushion padding, comforters and in stuff pillows

• Woven polyester fabric is used in home furnishing

• Medical Implants

• In jet engines as abradable seal

• Spun together with natural fibres to give strength

• Useful in making of films and bottles

• Also useful in holograms, liquid crystal displays, filters and tarpaulin

• Useful in insulating tapes, film insulation for wire and dielectric film for capacitors

• In auto-body fillers, casting materials and fibreglass laminating resins (because of thermosetting property)

• Useful in finishing of high quality wooden products

Acrylic fibre
Introduction 
Acrylic fibre is a synthetic fibre, which is made from polymer. Methyl acrylate and vinyl acetate are comonomers of acrylic fibre. This polymer is obtained by free radical polymerization. Acrylic fibre has wool like feeling and it is light weight, warm and soft.

Properties

• Resistant to moths, chemicals and oils

• Resistant to deterioration from sunlight exposure

• It dyes well

• Has excellent colorfastness

• It retains its shape

• Resists wrinkles and shrinkage

• Quick dry and easy care

• Very good heat retention

• Durability and quick dry qualities

• Quick water transport and weather resistant

Application of Acrylic fibre

• Use in the knitwear section

• In sportswear

• In industry and apparel

• Hygienic, barrier cloth and bactericidal

• Domestic textiles

• Cement reinforcement

• Producer dyed fabrics

• Carpet

Protein fibre
Introduction
Protein fibre is available in chitin and chitosan form. It has a chemical structure which is very similar to rayon. Chittin/chitosan is natural polysaccharide produced biologically by the living organisms on the earth. It is white porous polysaccharide. It is safe material to use and widely used in the different applications.

Properties

• Antimicrobial activity (Inhibits bacterial growth)

• Flocculation (Purifies waste waters)

• Salt adsorption (Lowers high blood pressure)

• Hemostatic action (bleeding easily stopped)

• Heavy metal adsorption (Adsorbs and removes radioactive substances)

• Cell activation (Promotes Iysozyme secretion)

• Slow releasing action (permits slow and steady release of medicines)

• Immunization (enhances immunity of body against diseases)

• Lowering of cholesterol (catches cholesterol and lowers its level)

• Biodegradation (being organic material it is degraded by microorganisms)

• Acceleration of skin tissue regeneration (thin non woven fabric is applied to burns)

• Oil absorption inhibition (helps to remove excess fat from body)

• Body activation (helps in wound healing)

Application of Protein fibre

Gymnastic uniform like sweats, t-shirts and shirts, polo shirts, blouse, cardigan

House interior like pillow cover and bedcover

Sports wear like uniform of baseball team, underwear for judo, wristband, socks with five toes

Underwear like bikini, lingerie and mens brief

Outer wear like blankets

Nylon Fibre
Introduction: A manufactured fibre in which the fibre forming substance is a long-chain synthetic polyamide in which less than 85% of the amide-linkages are attached directly (-CO-NH-) to two aliphatic groups. This is the definition of Nylon fibre by Federal Trade Commissions. The properties of Nylon fibre are as follows:

Properties:

• Dries quickly

• Easy to launder

• Strong and elastic

• Responsive to heat setting and resilient

• Retains its shape

• Polyamide 6 nylon6 PA-6 has thermoplastic property

• Lower mould shrinkage

• Good fatigue resistance

Application of Nylon Fibre:

• Used in hosiery

• Useful in making of swimwear, windbreakers, draperies, bedspreads, shorts track pants and active wear

• Also use in parachutes

• Useful in making of combat uniforms, flak vests, tires and life vests

• Nylon 6/6 is used in rollers, gears, nut and bolts, cams, bearings, electrical connectors, coil formers, kitchen utensils, combs, fuel tanks of cars and power tool housings

• Nylon 6/10 is useful in electrical components like bobbins, coil formers, tubing and wire jacketing

Glass Fibre
Introduction: Glass fibre is obtained from the fine fibres of the glass. Fibre glass is formed from fine silica strands. Glass itself is a crystalline solid. Basically glass fibre is a polymer. The common properties of glass fibre are as follows.

Properties

• High strength

• Non flammable

• Relatively insensitive to moisture

• Good electrical insulation

• High production rates

• Relatively low density

• Good chemical resistance

• Relatively low fatigue resistance

• Good strength properties in various conditions

• Relatively low density

• Low modulus

• Good electrical resistance

• Low cost

Application of Glass fibre

• Reinforcement material in polymer matrix composites

• Laminate structures can be used in storage tanks

• Woven fabrics are used in production of surfboards, composite panels and other similar devices

• Useful for good thermal insulation

Carbon Fibre:
Introduction: Carbon fibre is a well known textile material. In this graphite crystalline structures are arranged in a manner that it gives fibrous material. Carbon fibre is also available by oil/coal pitch after giving them certain heat treatment. It is broadly divided into the categories like, PAN-based carbon fibre, Pitch based carbon fibre, Mesophase pitch based carbon fibre, isotropic pitch based carbon fibre, Rayon-based carbon fibres and gas-phase-based carbon fibres. The properties of carbon fibre are as follows:

Properties:

• Physical strength

• Specific toughness

• Light weight

• High dimensional stability

• Low coefficient of thermal expansion

• Low abrasion

• Good vibration strength, damping and toughness

• Biological inertness and x-ray permeability

• Chemical inertness

• High corrosion resistance

• Fatigue resistance, self-lubrication, high damping

• Electrical conductivity

• Electromagnetic properties

Application of Carbon Fibre:

• Sporting goods, aerospace, marine and road transport

• Pickup arms, audio equipment, robot arms, Hi-fi equipment and loudspeakers

• Medical applications in x-ray and surgery equipment, ligament and tendon repair and in implants

• Nuclear field, chemical industry, pumps, seals, valves and its components in process plants

• Textile machinery, genera engineering

• Radiological equipment

• Large generator retaining rings

• Novel tooling, brushes, automobile hoods casings and bases for electronic equipments

• EMI and RF shielding

• Missiles, aircraft brakes, aerospace antenna and support structure,

• Large telescopes, waveguides for stable high-frequency (GHz) precision measurement frames and optical benches

Polyethylene
Introduction: Polyethylene is a polymer. Many no. of ethylene monomers join with each in the synthesis of polyethylene polymer. Polyethylene is obtained by the polymerization of ethane. Cationic coordination polymerization, anionic addition polymerization, radical polymerization and ion polymerization are the different methods by which polyethylene can be produced. Every method gives different types of polyethylene. Mechanical properties of Polyethylene depend on the molecular weight, crystal grouping and branching. Some properties are as follows:

Properties:

• Very good ultra violet resistance

• Excellent electrical and chemical resistance

• Low moisture absorption level

• Very good abrasion resistance

• Low specific gravity

• Higher energy is needed to break because of specific modulus and high specific strength

Application of polyethylene

• Medical implants

• Cable and marine ropes

• Sail cloth

• Composites like Pressure vessel boat hulls, sports equipment, impact shields

• Fish netting

• Concrete reinforcement

• Protective clothing

• Can be used in radar protective cover because of its low dielectric constant

• Can be used as a lining material of a pond which collects evaporation of water and containment from industrial plants

• Useful in geotextile applications

Polypropylene
Introduction: Polypropylene is a polymer made from addition of many propylene monomers. It has good resistant capacity to many acids, bases and chemical solvents. Its melting point is 160 °C (320 °F) so it is used in plastic materials for medical laboratories as an autoclave. Thin sheets of polypropylene are also used in dielectrics. Some properties of Polypropylene are given below:

Properties:

• Thermoplastic property
• Good strength
• Good environmental resistance
• Low density, hence light weight
• Good toughness
• Ability to be remoulded
Application of Polypropylene Fibre:

• Textile industry

• Good impact properties even at low temperatures and slightly increased elongation at break

• Extruded pipes, automotive like battery cases and bumpers, blow moulded containers

• Boat bodies, blow moulded medical articles and seat shells.

• Automotive Industry (load floors, valve covers, under engine covers, seat frames, front ends, battery trays, bumper beams, load floors and rocker panels)

• Aerospace Industry (overhead storage compartments and fuselage wall linings, fasteners, helicopter fairings, missile and aircraft stabilizer fins, engine housings, ducting, panels and wing ribs)

• Construction Industry (Thermosplastic composites for lightweight structural, pipes insulating panels, structural profiles and concrete rebars)

• Materials Handling (cargo containers and pallets)


Metal fibre 
Introduction
Metallic fibre is used in all kinds of clothes from everyday wear to party wear and evening wear. Metallic fibre is commonly used in upholestry. Basic types of metallic yarns are co-creating metallic yarns, m-type metallic yarn, mh-type metallic yarn, mx-type metallic yarn, s-type metallic yarn and st-type metallic yarn.

Properties

• Good thermal and electrical conduction
• Wear resistance and corrosion
• Elastic module and high intensity
• Protection from magnetism and static and radiation
• Better shield effect

Application of Metal fibre

• Automotive manufacturing
• Petrochemistry
• Environmental protection
• Automobile safe gasbag
• Shield dress of protection from magnetism
• Bulletproof vests
• Anti-fake material
• Dust proof ultra clean clothes

1 comment:

  1. Good post bro, keep it up. We are looking forward to your next posts....
    :)

    ReplyDelete