fibres

Fibres are slender, elongated bodies with a high length-to-diameter ratio, capable of being spun into yarns or formed into fabrics and other materials. They can be natural or synthetic and serve as the basic constituent of textiles, composites, filtration, and insulation.

Natural fibres include plant fibres such as cotton, flax (linen), jute, and hemp; animal fibres such as wool, silk, and cashmere; and, in some classifications, mineral fibres like asbestos (historically) though asbestos is hazardous and is now restricted. Natural fibres vary in strength, stiffness, moisture absorption, and fibre diameter.

Synthetic or man-made fibres are produced by chemical processes. Examples include nylon, polyester, and acrylics, as well as regenerated fibres such as viscose and lyocell from cellulose. Fibres are produced as filaments or as staple fibres by spinning processes such as melt spinning, dry spinning, or wet spinning; filaments can be cut into staple lengths.

Properties of fibres are influenced by molecular structure, crystallinity, orientation, and cross-section. Common descriptors include tenacity (strength), modulus (stiffness), elongation, and moisture regain. Measurements such as denier or tex describe linear density. Applications range from textiles and apparel to composite reinforcement, filtration, and insulation.

In manufacturing, fibres are often blended to combine properties. Finishing, dyeing, and texturizing modify performance. Environmental considerations include energy use in synthesis, recyclability or biodegradability, and microplastic release from some synthetic fibres.