5.3.2. Manufactured Fibres (also called man-made fibres)

Most of you must have seen a cotton flower with fibres sticking to the seeds, or sheep with long overgrown hair. You can also imagine how these may be used for yarn and fabric production. However, you may find it difficult to understand how the manufactured or synthetic fibres came to exist.

Manufactured fibres, also known as man-made fibres, are not found naturally like cotton or wool. Instead, they are created through industrial processes. The introduction of manufactured fibres actually stems from the desire to replicate natural fibres, particularly those like silk. Early experiments sought to mimic how silk is produced by silkworms, which spin silk from a liquid that hardens into a filament.

Think of it like cooking: just as chefs combine ingredients to create a dish similar to our favorites, scientists combine chemicals to create fibers that mimic the nature of silk, resulting in fabrics that are soft and luxurious.

The first manufactured fibre–Rayon–was commercially produced in AD 1895, while most others are products of the 20th century.

Rayon was the first successful synthetic fibre, marking the starting point for the production of manufactured fibres. The process of making these fibres grew throughout the 20th century, leading to a variety of new materials that became popular for textiles. Understanding this historical context helps students recognize the evolution of fabric production and its ties to human innovation.

Consider the evolution of technology: just like smartphones have evolved from early mobile phones, textiles have evolved with new fibers, starting with Rayon as a groundbreaking development in fabric technology.

The earliest manufactured fibres were made by modifying a non-fibrous material into a fibrous form. These were mainly from cellulosic substances like cotton waste or wood pulp. The second group of fibres were synthesised completely from use of chemicals. Whatever may be the raw material the basic steps for converting it into a fibrous form are the same. • The solid raw materials are converted into a liquid form of a specific viscosity. This may be due to a chemical action, dissolution, heat application or a combination action. This is called the spinning solution. • This solution is passed through a spinnerette – a small thimble shaped nozzle with a series of very small holes, into an atmosphere which hardens it or coagulates it into fine filaments. • As the filaments harden they are collected and stretched for further fineness and orientation or subjected to further processing like texurisation to improve its stretch and/or bulk characteristics.

The production of manufactured fibres starts with raw materials. First, these materials are turned into a liquid form, which allows them to be processed. This liquid is then pushed through a device known as a spinnerette, which shapes it into fine threads. Once the threads are formed and solidified, they may be stretched or further treated to enhance their texture and elasticity. This entire process is crucial for creating a versatile range of fibres.

Imagine a chef making pasta: they mix flour and water to create a dough, which is then pushed through a pasta maker to form noodles. In the same way, raw materials are processed to create threads for fabrics.

(a) Regenerated cellulosic fibres: Rayon–cuprammonium, viscose, high-wet-modulus (b) Modified cellulosic: Acetate–secondary acetate, triacetate (c) Protein fibres: Azlon (d) Non-cellulosic(synthetic) fibres (i) nylon (ii) polyester – terelene, terrene (iii) acrylic – Orlon, cashmilon (iv) modacrylic (v) spandex (vi) rubber (e) Mineral fibres (i) Glass – fibreglass (ii) Metallic – lurex.

Manufactured fibres can be categorized into different types based on their compositions. Regenerated fibres like rayon come from natural materials but are chemically processed. Modified cellulosic fibres like acetate undergo additional treatments to enhance their properties. Synthetic fibres such as nylon and polyester are entirely made from chemicals and have specific uses due to their durability and resistance. Each of these categories has unique characteristics that influence how they can be used in fabric.

Think of different types of chemicals in a science lab: just like scientists combine various chemicals to create different products, textile engineers create distinct types of fibres for specific applications.

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