More Related Content
Similar to fs.pptx
Similar to fs.pptx (20)
Recently uploaded
Recently uploaded (20)
fs.pptx
- 1. Textile Science National Institute of Fashion Technology, Gandhinagar
- 2. Objectives 2 To understand properties of textile fibers To enlarge vocabulary of textile fibers To keep up with advance in textile fibers To grasp basic theory related to textile fibers
- 3. Course Syllabus Textbook/ 1. Fabric Science,by Pizatto, Allen Cohen 2. Textile Fibers To fabric by Corbman 3. Understanding Fabrics from fibres to finished cloth by Debbie and Giollo 4. Understanding Textiles by Phyllis G, Tortora And Billie J Collier 5. Mordern Textiles by Dorothy Siegert Lyle 3
- 5. Topical Outline -1 5 Introduction to Textile Fibers 1 Natural Cellulosic Fibers 2 Natural Protein Fibers 3 Regenerated Fibers 4
- 6. Topical Outline -2 6 Synthetic Fibers 5 Absorption of Textile Fibers 6 Other properties of Textile Fibers 7
- 7. 1 Introduction to Textile Fibers What is a fiber Large L/D Small ; flexible Textile Fiber Length > 12.5 mm Strong ; processed Fiber Yarn Textile 7
- 8. 1.1 Classification of Textile Fibers 8 Cellulosic fibers Protein fibers Mineral fibers Regenerated fibers Synthetic fibers Mineral fibers Nature fiber Man-made fiber
- 9. 1.1.1 Natural cellulosic fibers Seed fibers: Bast fibers: Leaf fibers: Nut fibers: 9 cotton, kapok jute, hemp, ramie, flax Agave , pineapple, abaca Coir
- 10. 1.1.2 Protein fibers Animal-hair fibers: Animal secretion: 10 wool, specialty hair, fur fibers silk, spider silk
- 11. 1.1.3 Mineral fiber Asbestos 11 A group of minerals Heat, electricity and chemical damage resistance; sound absorption Highly toxic mesothelioma and asbestosis.
- 12. 1.1.4 Regenerated Fibers Regenerated cellulosic fibers Tencel Modal PLA Regenerated protein fibers Soybean fiber Milk fiber 12
- 13. 1.1.5 Synthetic Fibers Name Year Company Nylon 1938 Du pont Acrylic fiber 1950 E.I. Du Pont Polyolefin/ polypropylene 1959 Hercules Incorporated Spandex 1961 E. I. Du Pont 13
- 14. 1.1.6 Fineness of Fiber Gravimetric (Direct system) Tex: Mass in grams of 1000 m of fiber Denier: Mass in grams of 9000 m of fiber Metric count Ne (Indirect system): The length of meters per gram. 14
- 15. 1.1.7 Yarn Number System 15 Direct system Tex Indirect system Den(ier) Imp. count Metric count
- 16. 1.2 Fiber polymer Polymerization Degree of polymerization Average molecular weight of polymer = Molecular weight of thr repeating unit in the polymer 16
- 17. 1.2.1 Types of Polymer 17 Homopolymer Copolymer
- 18. 1.2.2 Interpolymer Forces of Attraction Van der Waals’ forces Hydrogen bonds Alt linkages Cross-links 18
- 19. 1.3 Fiber Properties 19 Fiber properties Physical Mechanical Chemical
- 20. 1.3.1 Physical Properties 20 Color Luster Shape White or colorless fibers and filaments are preferred. Varied in fibers Be examined both in cross section and in its longitudinal.
- 21. 1.3.2 Mechanical Properties 21 Mechanical Properties Tensile Flexibility Abrasion Resiliency Pilling Tenacity
- 22. 1.3.3 Chemical Properties Absorbency Effect of Heat Flammability Chemical Reactivity and Resistance 22
- 23. 2 Natural Cellulosic fibers 23 Stem Natural Cellulosic fibers Leaf Seed flax hemp jute ramie sisal abaca cotton kapok
- 24. 2.1 Introduction 24 Relatively high density Good conductor of heat and electricity Tend to burn easily Good resistance to alkalis Insects do not attack cellulosic fibers
- 25. 2.2 Cotton 25 Most widely used Cotton Grow in 80 countries Ideal for textiles Favorable personal care items
- 26. 2.2.1 Cotton classification 26 Breed Process Luster Upland Island Asian African roller ginned saw ginned White Yellow Grey
- 27. 2.2.2 Cotton Fiber Morphology 27 Cross-section Longitudinal section Kidney-shaped Convolution
- 28. 2.2.3 Structure of Cotton Fiber 28 Cuticle Primary wall Secondary wall Lumen
- 29. 2.2.4 Polymer System 29 Linear cellulose polymer Polymer System DP = 5000 Crystallinity = 65-70% (C6H10O5)n
- 30. 2.2.5 Chemical Properties 30 Weakened and destroyed by acids Resistant to alkalis Relatively unaffected by laundering
- 31. 2.2.6 Physical Properties 31 Relatively inelastic Physical Properties Very absorbent Conduct heat energy
- 32. 2.2.7 Growth and Production 32 Preparation Planting Crop Harvesting Ginning
- 33. 33
- 34. 2.3 Bast fibers Be collected from Phloem (the "inner bark" or the skin) or bast surrounding the stem of a certain, mainly dicotyledonic plants. 34 Bast fiber Flax Ramie Jute Hemp
- 35. 2.3.1 Flax Fiber 35 Cellulose Flax fiber Bast Multi-cellular Density = 1.50 g/cm3
- 36. 2.3.1 Flax Fiber Morphology 36 Cross-section Longitudinal section Polygonal Nodes
- 37. 2.3.2 Polymer System 37 Cellulose polymer Polymer System DP = 18000 Crystallinity > 70%
- 38. 2.3.3 Physical Properties 38 Very inelastic Physical Properties Very absorbent Best heat resistance Very strong
- 39. 2.3.4 Chemical Properties 39 Weakened and destroyed by acids Resistant to alkalis Relatively unaffected by laundering Not mercerized
- 40. 2.3.5 Processing of Flax 40 Pulling Retting Breaking Hackling Spinning
- 41. 3 Natural Protein Fibers 41 Hair Natural protein fibers Secretion wool cashmere mohair rabbit hair silk tussah silk spider silk
- 42. 3.1 Introduction 42 Be obtained from animal sources Excellent moisture absorbency Poor resistance to alkalis Good resiliency and elastic recovery
- 43. 3.2 Wool 43 Wlna, wullo, wull Wool fleece of sheep medium weight multi-cellular staple fiber
- 44. 3.2.1 Fiber Morphology 44 Cross-section Longitudinal section oval over-lapping scale
- 45. 3.2.2 Felting of Wool 45 High resilience Scales Directional friction Felting Wet and heat Dimensional stability Warm ,soft √ ×
- 46. 3.2.3 The Polymer System 46 Linear, keratin polymer has a helical configuration Unit of wool polymer is amino acid
- 47. 3.2.4 Structure of Wool Wool fiber is composed of surface scale, cortex and medulla layer. 47
- 48. 3.2.5 Chemical Properties 48 Resistant to acids Dissolve readily in alkaline solutions Yellow in sun and weather Easy to dye
- 49. 3.2.6 Physical Properties 49 weak Physical properties very absorbent low heat resistance excellent resilience
- 50. 3.3 Specialty hairs Mohair Cashmere Camel Hair Alpaca Llama Vicuna 50
- 51. 3.3.1 Mohair Mohair refers to the hair of Angora goat. Mohair fiber is approximately 25-45µm in diameter. It is both durable and resilient. It is notable for its high luster. 51
- 52. 3.3.2 Cashmere Cashmere is a type of fiber obtained from the Cashmere goat, or Pashmina. cashmere fiber is highly adaptable. Cashmere is similar to wool in most properties. 52
- 53. 3.3.3 Camel Hair Camel-hair are both light in weight and warm; they have a distinctive golden brown colour with a pleasing lustre. The fabrics are soft, comfortable, and good wearing, and they drape attractively. 53
- 54. 3.3.4 Alpaca Alpaca offers excellent warmth and insulation. The fibres are strong and glossy and make fabrics similar in appearance to mohair. 54
- 55. 3.3.6 Llama Llama fibre is soft, strong, and relatively uniform in length and diameter but somewhat weaker than alpaca or camel hair. 55
- 56. 3.3.7 Vicuna Vicuna is one of the softest fibres in the world. It is fine and lustrous, has a lovely cinnamon brown or light tan colour, and is strong enough to make very desirable fabrics. It is also very light in weight and very warm. 56
- 57. 3.4 Silk 57 secretion of silkworm Silk medium weight density 1.34 g/cm3
- 58. 3.4.1 Fiber Morphology 58 Cross-section Longitudinal section rounded triangle smooth
- 59. 3.4.2 Polymer System 59 linear fibroin polymer sixteen different amino acids not contain sulphur only in beta-configuration
- 60. 3.4.3 Chemical Properties 60 More readily affected by acids Swell in alkaline solutions Be affected by bleaches Resistance to sunlight is poor Compared with wool
- 61. 3.4.4 Physical Properties 61 strong Physical Properties more sensitive to heat more plastic than elastic
- 63. 4 Regenerated Fibers 63 Natural material Dissolve Extrude Wood, cotton Regenerated fibre Viscose, acetate, triacetate
- 64. 4.1 Viscose Fibres 64 viscose rayon cellophane viscose fibre Viscose process was discovered and patented in 1891 by C. F. Cross and E. J. Bevan.
- 65. 4.1.1 Manufacture pulp alkali cellulose xanthate cellulose viscose viscose filaments 65
- 66. 4.1.2 Modified Viscose Fibres 66 HVM rayon modified rayon HT rayon high wet modulus HWS rayon high wet strength High tenacity
- 67. 4.1.3 Polymer System 67 cellulose polymer Polymer system amorphous 65-60% crystallinity 35-40%
- 68. 68
- 70. 4.1.4 Physical Properties 70 weak Physical properties most absorbent low heat resistance limp
- 71. 4.1.5 Chemical Properties 71 similar to cotton sensitivity to acid, alkali, bleach, sunlight color more brightly
- 72. 4.2 Acetate and Triacetate 72 Cellulose Acetate Triacetate acetylize textile filtration
- 73. 4.2.1 Structures 73 DP= 250-300 Structures Skin-core structure Cross-section: lobed
- 74. 4.2.2 Properties 74 Acetate Triacetate hydrophilic thermoplastic hydrophobic high crystallinity Wrinkle easily in hot water Swells in water Resist to weak alkali and acids
- 75. 5 Synthetic Fibers 75 coal natural gas petroleum extrusion spinnerets Synthetic Fibers
- 76. 5.0 Types of spinning methods 76 melt polymer to a viscosity suitable for extrusion polymer solution is extruded into gas or vapor Melt Spinning Dry Solvent Spinning Wet Solvent Spinning Polymer solution is extruded into a precipitation bath
- 77. 5.1 Nylon 77 February 28, 1935 Wallace Carothers Nylon thermoplastic silky material polyamides DuPont
- 78. 78
- 79. 5.1.1 Types 79 mostly small amount Nylon 6 Nylon 6,6 Nylon 3, Nylon 4, Nylon 5, Nylon 7, Nylon 8, Nylon 12, Nylon 4,6, Nylon 6,10
- 80. 5.1.2 Structures 80 linear zigzag molecules structures crystallinity:65~86% H-bond amide group
- 81. 5.1.3 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. Abrasion resistance: high Water absorption: highest among all synthetic fibers 81
- 82. 5.1.3 Properties 82 high tenacity high elongation high recovery high abrasion resistance highest water absorption
- 83. 5.2 Polyester 83 DuPont, 1945 Polyester versatility Dacron, Tetoron Terelenka, Lavsan the largest volume 聚酯
- 84. 5.2.2 Types 84 Polyethylene terephthalate Polybutylene terephthalate PET PBT PTT Polybutylene terephthalate
- 86. 5.2.4 Structures 86 DP =115-140 structures crystallinity: 35% even diameter very oriented
- 87. 5.2.5 Properties 87 high tenacity high failure elongation low compressional resilience very low moisture regain high electrical resistivity
- 88. 5.2.6 Modification 88 High tenacity higher crystallinity and DP Sheath-core polyester core, low melt polymer sheath Coolmax hydrophilic treated Wicking
- 89. 5.3 Acrylic 89 1950, DuPont Acrylic synthetic wool Perlon, Orlon
- 90. 5.3.1 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 90
- 92. 5.3.3 Properties 92 medium tenacity medium failure strain high elastic recovery moderate abrasion resistance
- 93. 5.4 Elastomeric 93 polyurethane-based Elastomeric lightest apparel fibre H2NCONH2
- 94. 5.4.1 Fibre Morphology Longitudinal appearance has distinct striations and specks. Cross-section of fiber has the dump-bell or dog-bone shape 94
- 95. 5.4.2 Polymer System Two types of elastomeric polymers are synthesized. Each is extruded into filaments with excellent elastic properties but differing in their resistance to alkalis. The polyether type (for example Lycra) resistant to alkalis The polymer type (for example, Vyrene) 95
- 96. 5.4.3 Physical Properties 96 weak tenacity excellent recovery hydrophobic thermo-plastic
- 97. 5.4.4 Chemical properties Effect of acids: Elastomeric textile material in general are resistant to acids. Effect of alkalis: The elastomeric is sensitive to alkalis. Colour-fastness: Elastomeric textile material tend to be difficult to dye owing to the hydrophobic and very crystalline nature of their polymer system. 97
- 98. 5.4.4 Chemical Properties 98 resistant to acids Chemical properties difficult to dye sensitive to alkalis
- 99. 6.1 Introduction of Absorption Adsorption in a non-swelling medium, for example, the adsorption of gases on charcoal, is a comparatively simple process, but the absorption of water by fibers is an example of a process that comes midway between these two and partakes of some features of each. 99
- 100. 6.2 Equilibrium When a textile material is placed in a given atmosphere, it takes up or loses water at a gradually decreasing rate until it reaches equilibrium, when no further change takes place. This is a dynamic equilibrium. 100
- 101. 6.3 Regain and relative humidity Relative humidity(RH)= p(H2O)－Partial pressure of water vapor p*(H2O)—Saturation vapor pressure Regain G － Mass of undried specimen G0 －Mass of dried specimen 2 * 2 (H O) 100% (H O) p p 0 0 100% G G W G 101
- 102. 6.3 Regain and relative humidity 102 0 0 100% G G W G 2 2 (H O) * (H O) 100% p p
- 103. 6.4 Theories of moisture sorption Sorption refers to the action of either absorption or adsorption. As such it is the effect of gases or liquids being incorporated into a material of a different state and adhering to the surface of another molecule. 103
- 104. 6.4.1 The effect of hydrophilic groups As absorption, we take account of interac- tion between water molecules and molec- ules of the fiber. All the natural animal and vegetable fibers have groups in their molecules that attract water, such as –NH2, —CONH, —OH, —COOH. 104
- 105. 6.4.2 Directly and Indirectly Attached Water The first water molecules are absorbed directly onto hydrophilic groups, but, for the others: They may be attracted to other hydrophilic groups, or they may form further layers on top of water molecules. H2O H2O H2O H2O H2O H2O Fiber Direct Indirect H2O H2O 105
- 106. 6.4.3 Absorption in crystalline regions In crystalline region, the fiber molecules are closely packed together in a regular pattern. Thus it will not be easy for water molecules to penetrate into a crystalline region, and, for absorption to take place, the active groups would have to be freed b y t h e b r e a k i n g o f c r o s s - l i n k s . 106
- 107. 7 Other Properties of Textile Fibers 107 Thermal Electric Optical Performance of processing and usage of textile fibers
- 108. 7.1 Thermal properties Thermal conductivity is a property of materials that express the heat flux(W/m2) that will flow through the material if a certain temperature gradient DT(K/m) exists over the material. Fiber material Thermal conductivity[mW/(m.k] Cotton 71 Wool 54 Silk 50 108
- 109. 7.1.1 Specific Heat Capacity 109 Q C m T Specific heat capacity (J/(g˙℃) Heat, （J） Temperature(℃) Mass(g) moisture temperature fiber structure C
- 110. 7.1.2 Coefficient of Heat Conductivity 110 Q d T t s Coefficient of heat conductivity (W/(m˙℃) Conduction surface （m2） Temperature difference ℃) Heat, (J） Thickness, (m） Time,(t）
- 111. 7.2 Optical properties When light falls on a fiber, it may be partly transmitted, absorbed or reflected. Refractive index niso of an isotropic fiber is given by the mean of the refractive indices of an oriented fiber in 3 directions: Polarized parallel to fiber axis Polarized perpendicular to fiber axis 1/ 3( 2 ) iso n n n n n 111
- 113. 7.2.1 Luster 113 Light on collection of fibers Laminate structure Longitudinal morpha Cross-sectional shape Luster
- 114. 7.2.2 Birefringence Birefringence, or double refraction, is the decomposition of a ray of light into the ordinary ray and the extraordinary ray when it passes through certain types of material. 114 n n n P Birefringence index Refractive index for light polarized parallel (perpendicular)to the fiber axis.
- 115. 7.3 Electric properties The electronic properties of fibers are of less importance than the mechanical properties. 115 electric conduction dielectric static electricity
- 116. 7.3.1 Electric Conduction 116 Surface resistivity Volume resistivity Mass resistivity Fiber Cotton 6.8 Ramie 7.5 Silk 9.8 Wool 8.4 Viscose 7.0 Fiber Polyamide 9-12 Acetate 11.7 Acrylic 8.7 Polyester 8.0 lg m lg m
- 117. 7.3.2 Dielectric 117 Fiber is dielectric material. 0 r C C