Fiber
A fiber is a long, thin strand or thread of material, typically with a length at least 100 times its diameter, that can be spun into yarn and processed into fabrics or other structures.[1] Fibers are broadly classified as natural, derived from plants (e.g., cotton, flax), animals (e.g., wool, silk), or minerals (e.g., asbestos), or man-made, produced through chemical synthesis (e.g., polyester, nylon) or regeneration from natural polymers (e.g., rayon).[2] Fibers serve as the fundamental building blocks for textiles, apparel, and industrial applications such as composites, ropes, and filtration materials. Their properties, including strength, flexibility, and durability, determine suitability for various uses.[3]Overview
Definition and Characteristics
A fiber is defined as a long, thin strand or thread of material characterized by a high aspect ratio, typically greater than 100 (length-to-diameter ratio), which enables it to be spun, woven, or otherwise processed into yarns or fabrics.[1] This elongated structure distinguishes fibers from other forms of matter, such as particles or films, and is fundamental to their utility in applications like textiles and composites.[4] Key characteristics of fibers include tensile strength, which measures their resistance to breaking under tension; flexibility, allowing them to bend repeatedly without fracturing; and elongation, the extent to which they can stretch before breaking.[5] Fibers also exhibit a typical diameter ranging from 1 to 100 micrometers, influencing their fineness and handling properties, and crystallinity, referring to the degree of ordered molecular arrangement that affects overall strength and durability.[6] Fibers are classified based on origin into natural (derived from plants, animals, or minerals) and man-made (produced through chemical or mechanical processes); by chemical composition into organic (carbon-based polymers) and inorganic (such as glass or metal oxides); and by structure into monofilament (a single continuous strand) or multifilament (multiple strands bundled together).[2] These frameworks provide a basis for understanding fiber behavior and selection in various contexts. Common fiber forms include staple fibers, which are short lengths (typically under 100 mm) suitable for spinning into yarns, and continuous filaments, which are indefinitely long and can be directly used or converted into multifilament yarns or nonwoven structures through bonding rather than weaving.[7]Historical Development
The use of natural fibers dates back to prehistoric times, with the earliest known evidence consisting of twisted flax fibers discovered in a cave in the Republic of Georgia, dating to approximately 34,000 years ago. These artifacts, found alongside stone tools and bone implements, indicate early human manipulation of plant materials for cordage or rudimentary textiles. In ancient China, silk production emerged around 2700 BCE, as evidenced by silk fabrics from the Neolithic site of Qianshanyang in Zhejiang Province, marking the beginning of sericulture and the domestication of silkworms for fiber extraction.[8] Similarly, cotton cultivation in the Indus Valley Civilization began around 5000 BCE, with archaeological remains of cotton fibers and seeds unearthed at the Neolithic site of Mehrgarh in present-day Pakistan, demonstrating early agricultural practices for textile purposes. The Industrial Revolution in the 18th century transformed fiber processing through mechanization, shifting production from artisanal to factory-based systems. In 1764, James Hargreaves invented the spinning jenny, a multi-spindle device that enabled one worker to spin multiple threads simultaneously, dramatically increasing wool and cotton yarn output and paving the way for textile mills. This was followed in 1785 by Edmund Cartwright's power loom, which automated weaving and further accelerated mass production, leading to the proliferation of mills in Britain and later globally, where steam power integrated spinning and weaving into large-scale operations. The late 19th century saw the advent of man-made fibers, beginning with regenerated cellulose. In 1892, chemists Charles Frederick Cross and Edward John Bevan developed viscose rayon, the first commercial semi-synthetic fiber derived from wood pulp, which was patented and produced on an industrial scale by the early 1900s. Synthetic fibers followed in the 20th century: Wallace Carothers at DuPont synthesized nylon in 1935, introducing the first fully synthetic polyamide fiber for textiles and later military uses. Polyester was invented in 1941 by John Rex Whinfield and James Tennant Dickson at the Calico Printers' Association in England, offering durable, wrinkle-resistant alternatives that quickly gained traction in apparel. Post-World War II innovations expanded high-performance fibers for specialized applications. In 1958, Roger Bacon at Union Carbide produced the first high-strength carbon fibers through pyrolysis of rayon precursors, enabling lightweight composites for aerospace. Aramids emerged in 1965 when Stephanie Kwolek at DuPont created Kevlar, a para-aramid synthetic fiber renowned for its exceptional tensile strength and heat resistance. In the 2010s, bio-engineered fibers advanced with recombinant production of spider silk proteins in transgenic silkworms and bacteria, yielding materials with superior toughness for biomedical and protective uses. Key institutional developments included the establishment of the International Wool Textile Organisation (IWTO) in 1931, which promoted standards and research in wool processing amid growing competition from synthetics. The 1970s oil crises, by raising petroleum costs, temporarily slowed synthetic fiber expansion but ultimately reinforced their dominance through established infrastructure, as global textile consumption shifted toward affordable, versatile man-made options over natural fibers. In the 2020s, the focus has shifted towards sustainable man-made fibers, with recycled polyester comprising about 20% of production and growth in bio-based alternatives to address environmental impacts.[9]Natural Fibers
Vegetable Fibers
Vegetable fibers, derived from various parts of plants, represent a major category of natural fibers valued for their renewability and versatility in textiles and composites. These fibers are primarily classified based on their botanical origin within the plant structure: bast fibers from the phloem or inner bark of stems, leaf fibers from the leaves, and seed fibers from seed pods or capsules.[10][11] Bast fibers are extracted from the stems of dicotyledonous plants, where they form supportive bundles in the phloem tissue. Common examples include flax from Linum usitatissimum, hemp from Cannabis sativa, and jute from species of Corchorus. Extraction typically involves retting—such as water or dew retting—to separate the fibers from non-fibrous tissues, followed by decortication to remove the outer bark and break the stem.[11][12] Flax, in particular, has a long historical association with linen production, dating back over 30,000 years to prehistoric dwellings and serving as a primary textile material in ancient Egypt for clothing and sails. Jute, often used in burlap and packaging, sees its production dominated by India and Bangladesh, which together account for over 90% of global output, with India producing approximately 2 million tonnes annually as of 2024.[13][14][15] Leaf fibers are obtained from monocotyledonous plants, specifically the fibrous bundles in leaf tissues. Notable types include sisal from Agave sisalana and abaca from Musa textilis, both part of the Agave and banana families, respectively. These are extracted through mechanical processes like crushing the leaves to release the fibers and scraping away the pulp, yielding long, strong strands suitable for ropes and twine.[10][13] Seed fibers originate from the hairy coverings or linings of seed pods. Cotton, derived from species of Gossypium, is the preeminent example, with global production reaching approximately 25.9 million tonnes in the 2024/25 season, far surpassing other vegetable fibers. Kapok, from the seed pods of Ceiba pentandra, provides a softer, fluffy fiber used in insulation and stuffing. These fibers are typically harvested by ginning, which separates the lint from seeds.[16][17][13] In composition, vegetable fibers are predominantly cellulosic, with cellulose content ranging from 60-75% in bast fibers to 80-90% in cotton, accompanied by hemicellulose (10-20%), lignin (2-25%), and pectin as binding agents. This structure contributes to their high moisture absorption, often up to 8-10% under standard conditions, enhancing breathability in applications like apparel. However, the hydrophilic nature also renders them susceptible to microbial degradation in humid environments without chemical treatments like scouring. Their fully biodegradable composition allows breakdown in soil within months to years, depending on conditions, making them environmentally preferable for sustainable uses.[18][19] Vegetable fibers generally exhibit moderate tensile strength, with cotton around 300-500 MPa, supporting their role in everyday textiles.[20]Animal Fibers
Animal fibers are natural protein-based materials derived from various animals, primarily through harvesting their hair, fur, or secretions, and are valued for their warmth, durability, and biodegradability in textile applications. These fibers originate from biological structures such as keratin in mammalian hair or fibroin in insect cocoons, providing unique properties like elasticity and insulation that stem from their molecular composition and morphology. Harvesting techniques vary by source, often involving shearing, combing, or reeling to obtain raw fibers without harming the animal, though ethical considerations arise in some practices. Wool, the most prominent animal fiber, is harvested from sheep through annual shearing of their fleece, which consists primarily of keratin proteins forming over 90% of the fiber's composition. This keratin-based structure includes a crimped morphology that enhances interlocking and insulation by trapping air within the fiber assembly. Global production of wool reaches approximately 2 million tonnes annually in greasy form as of 2023, with major contributors including Australia and China. The crimp, typically featuring 4-5 waves per centimeter in fine wools, contributes to the fiber's resilience and ability to retain shape after processing.[21] Silk is produced by the larvae of the silkworm moth (Bombyx mori), where it forms cocoons composed mainly of fibroin protein, accounting for 70-80% of the raw material, coated by sericin gum. Harvesting involves boiling cocoons to kill the pupae and reel the continuous filaments, each up to 1,500 meters long, enabling the creation of smooth, strong yarns without spinning. China maintained a monopoly on silk production for nearly 3,000 years until the 6th century CE, when sericulture spread to the Byzantine Empire via trade routes. The triangular cross-section of silk filaments promotes luster by reflecting light at multiple angles, giving the fiber its characteristic sheen. Other notable animal fibers include cashmere and mohair, both sourced from goats via combing or shearing during seasonal shedding. Cashmere, the fine undercoat of cashmere goats, offers exceptional softness and warmth, while mohair from Angora goats provides luster and strength due to its longer, straighter guard hairs. Leather fibers, derived from animal hides such as those of cattle, are based on collagen proteins that form intertwined bundles, processed through tanning to create durable, non-woven sheets used in textiles and beyond. Angora wool from rabbits is harvested by plucking or shearing the undercoat, but this practice raises ethical concerns due to reports of painful live-plucking methods that cause skin irritation and stress to the animals. Unique traits of animal fibers include wool's elasticity, allowing up to 50% elongation before breaking, and its excellent thermal insulation from the crimped structure that minimizes heat loss. However, wool is prone to felting from scale overlap during agitation and damage from alkalis, which degrade the keratin proteins. Silk, in contrast, offers high tensile strength but lower elasticity compared to wool.Mineral Fibers
Mineral fibers refer to naturally occurring inorganic fibers derived from geological sources, primarily silicate minerals formed through metamorphic and hydrothermal processes in rocks such as serpentinites, limestones, and ultramafic formations. These fibers are distinguished by their crystalline structure, high thermal stability, and incombustibility, making them suitable for applications requiring heat resistance, though many pose health risks due to their fine, inhalable nature. Unlike organic natural fibers from plants or animals, mineral fibers lack biological origins and exhibit rigid, brittle characteristics with diameters often below 1 micrometer, contributing to their unique mechanical reinforcement potential in composites.[22][23][24] Asbestos represents the most prominent group of mineral fibers, consisting of six regulated types: chrysotile from the serpentine group and five amphibole varieties (actinolite-tremolite, amosite, anthophyllite, crocidolite, and tremolite-actinolite). These fibers form in metamorphic rocks through hydrothermal alteration of ultramafic or mafic parent rocks, where magnesium- and iron-rich minerals react with silica-rich fluids under elevated temperatures and pressures, typically producing veins or masses with fiber diameters ranging from 0.025 to less than 1 micrometer and lengths up to hundreds of micrometers. Chrysotile, the most abundant form (over 90% of historical production), has the composition Mg₃Si₂O₅(OH)₄, featuring a curled sheet structure that imparts flexibility, while amphiboles like crocidolite (Na₂Fe₃²⁺Fe₂³⁺Si₈O₂₂(OH)₂) exhibit straight, needle-like chains for greater rigidity. These silicate minerals demonstrate exceptional heat resistance, with chrysotile stable up to approximately 800°C before dehydroxylation and melting around 850°C, and amphiboles enduring similar or higher temperatures due to their anhydrous nature.[25][23][22][26][24] Historically, asbestos mining peaked in the 1970s, driven by demand for insulation and construction materials, with Canada (primarily Quebec's chrysotile deposits) and Russia (Ural Mountains' amphibole and chrysotile sources) accounting for over 50% of global output, reaching about 5 million tons annually worldwide by 1975. However, widespread recognition of health hazards—particularly the link to mesothelioma, a rare cancer of the lung lining—led to regulatory actions; the European Union implemented a comprehensive ban on asbestos mining and use in 1999, while the United States enacted a partial ban in 1989 targeting specific products like pipe insulation, though it was largely overturned in 1991, resulting in ongoing restrictions. In March 2024, the U.S. EPA finalized a ban on ongoing uses of chrysotile asbestos, but in July 2025, this was delayed by the Fifth Circuit Court for agency reconsideration, maintaining partial prohibitions as of November 2025. In the US, asbestos exposure contributed to approximately 2,500 mesothelioma deaths annually from 1999 to 2020, underscoring the fibers' carcinogenicity from inhalation of durable, biopersistent particles that trigger inflammation and genetic damage. Despite these traits, asbestos fibers are inherently brittle, prone to fracturing, and non-combustible, offering incombustibility up to their thermal limits but at the cost of severe respiratory risks.[22][27][28][29][30][31][32] Wollastonite, another key mineral fiber, is a calcium inosilicate (CaSiO₃) formed via contact metamorphism of siliceous limestones or dolomites at temperatures between 400°C and 800°C, where calcite reacts with quartz or silica under the influence of igneous intrusions, yielding acicular crystals that can be processed into fibers with aspect ratios up to 20:1. Composed primarily of 48% CaO and 51% SiO₂, with minor iron and magnesium substitutions, wollastonite exhibits low thermal expansion, high whiteness, and stability up to 1,120°C, making it thermally superior to many asbestos variants for insulation without the associated health hazards. Its needle-like morphology provides reinforcement similar to asbestos but with reduced brittleness and no documented carcinogenicity, positioning it as a safer geological alternative in ceramics and polymers.[33][34][33]Man-Made Fibers
Regenerated Fibers
Regenerated fibers are semi-synthetic materials produced by chemically processing natural polymers, primarily cellulose or proteins, to form new filaments with tailored properties. These fibers bridge the gap between natural and fully synthetic options, offering enhanced versatility while retaining some inherent biocompatibility from their biological origins. Unlike unmodified natural fibers such as cotton, regenerated variants undergo dissolution and reformation, resulting in smoother textures and improved processability.[35] Cellulose-based regenerated fibers dominate this category, with viscose rayon and lyocell as primary examples derived from wood pulp. Viscose rayon, the earliest commercial regenerated fiber, was invented in 1891 and entered production in 1905 through the xanthation process, where purified cellulose is treated with sodium hydroxide to form alkali cellulose, then reacted with carbon disulfide (CS2) to create cellulose xanthate, which is dissolved in a dilute sodium hydroxide solution to form viscose dope. This viscous solution is extruded through spinnerets into an acid bath, precipitating and regenerating the cellulose into continuous filaments.[36][35] Lyocell, developed in the 1990s, employs a more environmentally friendly closed-loop process using N-methylmorpholine N-oxide (NMMO) as a non-toxic solvent to directly dissolve cellulose pulp, followed by dry-jet wet spinning and solvent recovery exceeding 99% efficiency, minimizing waste and chemical emissions.[37][38] Lenzing AG leads in lyocell innovation under the Tencel brand, driving a sustainability shift from traditional viscose due to reduced environmental impact.[38] These fibers consist of over 95% regenerated cellulose, exhibiting a composition chemically identical to natural cellulose but with a smoother, more uniform surface that enhances drape and sheen compared to cotton. Variants like modal, a high-tenacity form of viscose, are produced by modifying the viscose process with extended steeping and higher cellulose purity, yielding fibers with superior wet strength retention—up to 85% of dry strength—making them suitable for durable textiles. Protein-based regenerated fibers, such as casein derived from milk proteins and azlon from soy or corn zein, were developed in the early 20th century but are now rare due to production challenges and competition from synthetics; casein fibers, prominent in the 1930s–1940s, involved dissolving skim milk casein in alkali and extruding into an acidic coagulating bath, offering wool-like softness before declining post-World War II.[39][40][41][42] Global production of rayon, primarily viscose, was approximately 7.9 million metric tons in 2023, underscoring its scale in the textile industry.[43] Regenerated cellulose fibers boast high absorbency with a moisture regain of about 11–13%, excellent dye affinity for vibrant colors, and breathability, though they suffer from reduced wet strength—losing up to 50% compared to dry conditions—which necessitates careful handling during processing. These traits position them as eco-conscious alternatives in apparel and hygiene products, emphasizing sustainability through renewable sourcing and recyclability.[44][45][46]Synthetic Fibers
Synthetic fibers are fully artificial organic polymers produced through chemical synthesis from petroleum-derived monomers, distinguishing them from regenerated fibers that modify natural polymers. These fibers are engineered for specific performance characteristics, enabling widespread use in textiles and industrial applications. The global production of synthetic fibers reached approximately 84 million tonnes in 2023, with polyesters dominating the market at around 55% share.[47] The primary types of synthetic fibers include polyesters, polyamides, acrylics, and olefins. Polyesters, particularly polyethylene terephthalate (PET), are synthesized via polycondensation of terephthalic acid and ethylene glycol, forming ester linkages in long polymer chains. PET accounts for the majority of polyester production, which exceeded 70 million tons globally by the early 2020s, reflecting its post-1950s rise driven by advancements in polymerization techniques. Polyamides, such as nylon 6/6, are produced by the condensation polymerization of hexamethylenediamine and adipic acid, resulting in amide linkages that provide strength and elasticity; nylon played a pivotal role in World War II, replacing silk in parachutes during the 1940s due to its durability and availability. Acrylic fibers are based on polyacrylonitrile, often used in modacrylic blends containing 35-85% acrylonitrile copolymerized with other monomers like vinyl chloride for enhanced flame resistance. Olefin fibers, including polypropylene and polyethylene, are formed through addition polymerization of propylene or ethylene monomers, yielding non-polar, hydrophobic chains suitable for moisture-resistant applications.[48][47][49][50][51][52] Synthesis of these fibers typically involves polymerization to create high-molecular-weight thermoplastics (10,000-100,000 g/mol), followed by extrusion into fibers. For nylon, condensation polymerization eliminates water to form amide bonds, while polypropylene relies on Ziegler-Natta catalyzed addition polymerization to add monomers across double bonds without byproducts. The resulting polymers exhibit semi-crystalline structures with 40-60% crystallinity, where ordered regions contribute to mechanical strength and amorphous areas allow flexibility. Melt-spinning is the dominant processing method, in which polymer pellets are heated to a viscous melt (typically 250-300°C), extruded through spinnerets to form filaments, and cooled to solidify, enabling efficient production of continuous fibers for most thermoplastics like PET and polypropylene.[53][54][55][56] Specialized synthetic fibers like spandex (also known as elastane) are polyurethane-based, synthesized by reacting diisocyanates with polyols to form segmented block copolymers with soft and hard segments, enabling exceptional elasticity of up to 500% stretch and recovery. Synthetic fibers offer unique traits such as high durability and wrinkle resistance due to their strong intermolecular forces and low friction, making them ideal for crease-resistant garments. However, they exhibit low moisture absorption—polyester regains only 0.4% moisture under standard conditions—leading to reduced breathability compared to natural fibers. Additionally, concerns over microplastic shedding have grown, as washing synthetic textiles releases microfibers into waterways, contributing to environmental pollution estimated at billions of particles annually; emerging regulations, such as the EU's 2025 restrictions on intentional microplastic releases, aim to mitigate this issue. While carbon-based variants exist for high-performance uses, they fall outside the organic polymer category detailed here.[57][58][59][60]Inorganic Specialty Fibers
Inorganic specialty fibers encompass a range of engineered non-organic materials designed for demanding applications requiring exceptional strength, thermal stability, and durability. These include carbon fibers, glass fibers such as E-glass, ceramic fibers like silicon carbide, metallic fibers, and basalt fibers as a mineral-derived variant. Unlike organic synthetics, these fibers derive their properties from inorganic compositions, enabling use in environments where organic materials would degrade.[61][62] Carbon fibers, the most prominent type, are produced primarily from polyacrylonitrile (PAN) or pitch precursors through a multi-stage pyrolysis process. The process begins with oxidation (stabilization) at 200-300°C to cross-link the precursor and prevent melting, followed by carbonization at 1000-1500°C in an inert atmosphere to remove non-carbon elements, and graphitization at 2000-3000°C for high-modulus variants to align graphite crystallites. The resulting fibers consist of 93-99% carbon, exhibiting tensile strengths of 3-7 GPa and Young's moduli of 200-600 GPa, which provide extreme stiffness suitable for aerospace and automotive composites. PAN-based fibers dominate production, accounting for over 90% of output due to their balance of strength and processability. The global carbon fiber market, valued at $5.75 billion in 2024, is projected to reach $10.68 billion by 2030, driven by demand in lightweight structures; Toray Industries holds a leading position with significant market share in advanced materials. However, their high production costs and inherent brittleness limit broader adoption, though they offer superior corrosion resistance in harsh conditions.[62][63][64][65][61][66][67][68] Fiberglass, particularly E-glass, is manufactured by melting a silica-alumina-borate composition (approximately 52-56% SiO₂, 12-16% Al₂O₃, and 16-25% CaO) at around 1400°C and drawing it into continuous filaments through platinum-rhodium bushings. This amorphous structure yields strong, insulating fibers widely used in reinforcements, with production pioneered by Owens Corning in the 1930s as a safer alternative to asbestos for electrical and thermal insulation applications. Silicon carbide (SiC) fibers, a key ceramic type, are derived from polycarbosilane precursors via spinning, curing, and pyrolysis at 1000-1300°C, resulting in beta-SiC crystallites that withstand temperatures up to 1600°C, making them ideal for aerospace turbine components. Metallic fibers, such as stainless steel (e.g., 316L grade), are produced by bundle drawing or melt spinning and integrated into textiles for electromagnetic shielding and conductivity, offering durability in corrosive environments. Basalt fibers, a hybrid from natural volcanic rock, involve melting basalt (46-52% SiO₂, 15-17% Al₂O₃) at 1450°C and extruding through dies, providing a cost-effective option with good tensile strength and alkali resistance, though still exhibiting the brittleness common to inorganic fibers. Overall, these fibers excel in corrosion resistance and high-temperature performance but face challenges from elevated costs and fragility under impact.[69][70][71][72][73][74][75]Fiber Properties
Mechanical and Physical Properties
Mechanical properties of fibers primarily encompass their response to tensile loads, including tenacity (specific strength), elongation at break, and initial modulus (stiffness). Tenacity, measured in grams per denier (g/denier) or centinewtons per tex (cN/tex), quantifies the force required to break a fiber per unit linear density, with typical values ranging from 2-5 g/denier for cotton to 8-10 g/denier for nylon.[76][77] Elongation at break, expressed as a percentage, indicates extensibility and varies widely from 5-10% for cotton to 20-50% for elastomeric fibers like spandex, reflecting their ability to deform before failure.[76][77] The initial modulus, also in g/denier, measures resistance to initial deformation and spans 50-200 g/denier across fiber types, with higher values denoting greater stiffness essential for load-bearing applications.[77] Physical attributes further define fiber behavior under mechanical stress. Fiber diameter typically ranges from 10-50 micrometers, influencing flexibility and packing density, while cross-sectional shapes vary: synthetic fibers often exhibit uniform round profiles for smooth processing, whereas natural fibers like wool display irregular kidney-bean shapes that enhance interlocking in yarns.[78] Density, a key indicator of mass efficiency, averages 1.3-1.5 g/cm³ for most organic fibers, with cotton at 1.54 g/cm³ and nylon at 1.14 g/cm³, affecting overall composite weight.[79] Surface friction, quantified by the coefficient of friction (typically 0.2-0.4 between fibers), governs inter-fiber interactions during spinning and weaving, with lower values in smooth synthetics reducing processing energy compared to scaly natural fibers like wool.[80] Standardized testing, such as ASTM D3822 for single-fiber tensile properties, evaluates these traits by mounting fibers in grips and applying controlled extension until breakage.[81] This method derives stress (\sigma = F / A), where F is force and A is cross-sectional area, and strain (\epsilon = \Delta L / L_0), where \Delta L is elongation and L_0 is initial length, enabling computation of tenacity, elongation, and modulus from load-elongation curves.[82] Comparisons across fiber types highlight trade-offs: natural fibers like silk offer balanced tenacity around 4.5 g/denier with moderate elongation (20-25%), while synthetics such as polyester provide higher tenacity (5-7 g/denier) but lower elongation (10-20%), suiting durable applications.[77] Synthetic fibers generally exhibit superior fatigue resistance under cyclic loading due to uniform structure, outperforming naturals like cotton which degrade faster from microcracks.[83] Specialty fibers like Kevlar achieve record tenacity of 28 g/denier, driven by highly aligned polymer chains.[84] Processing factors, such as drawing ratio during manufacturing, enhance these properties by promoting molecular alignment, often increasing modulus by 2-3 times in synthetic fibers.[85]| Fiber Type | Tenacity (g/denier) | Elongation at Break (%) | Initial Modulus (g/denier) | Density (g/cm³) |
|---|---|---|---|---|
| Cotton | 2-5 | 5-10 | 50-100 | 1.54 |
| Wool | 1-2 | 25-50 | 20-30 | 1.31 |
| Silk | 4.0-5.5 | 20-25 | 60-80 | 1.35 |
| Nylon | 4-9 | 20-40 | 20-50 | 1.14 |
| Polyester | 5-7 | 10-20 | 80-120 | 1.38 |
| Kevlar | 18-28 | 3-4 | 400-800 | 1.44 |