Several basic properties of textile fibers

1. The moisture absorption performance of fibers

When textile fibers are exposed to the air, they constantly exchange water vapor with the air, that is, they continuously absorb water vapor from the air while also constantly releasing it into the air.

The property of textile fibers to absorb or release water vapor is called the hygroscopicity of the fibers. Hygroscopicity is one of the important physical properties of textile fibers.

The degree of moisture absorption of textile fibers has a certain impact on the shape, size, weight and physical and mechanical properties of the fibers, and thus also affects their processing and application performance.

The moisture absorption capacity of textile fibers also directly affects the wearing comfort of the fabric. Fibers with high moisture absorption capacity can easily absorb the sweat excreted by the human body, regulate body temperature, relieve the feeling of dampness and stuffiness, and thus make people feel comfortable. Therefore, in commercial trade, fiber performance testing, textile processing and the selection of textile products, attention should be paid to the moisture absorption performance of fibers.

Among common textile fibers, wool, linen, viscose fiber, silk, cotton, etc. have relatively strong moisture absorption capabilities. The moisture absorption capabilities of synthetic fibers are generally poor. Among them, vinylon and nylon have slightly better moisture absorption capabilities, acrylic is slightly worse, polyester is even worse, and polypropylene and polyvinyl chloride have almost no moisture absorption.

At present, synthetic fibers with poor moisture absorption capacity are often blended with natural fibers or viscose fibers with strong moisture absorption capacity to improve the moisture absorption capacity of textiles.

Among the moisture absorption properties of fibers, apart from moisture absorption, the water absorption of fiber materials is also closely related to the wearing comfort of the fabric. The water absorption of fibers refers to the property of fibers to absorb liquid water.

2. Mechanical properties of fibers

The properties of various deformations of textile fibers under the action of various external forces are called the mechanical properties of textile fibers. External forces include various forms such as tension, compression, bending, torsion and friction.

The mechanical properties of textile fibers should include the strength, elongation, elasticity, wear resistance, elastic modulus, etc. of the fibers.

The strength of fibers: The strength of fibers refers to their ability to resist external force damage. To a large extent, it determines the durability of textile products.

The wear resistance of fibers: Fibers and their products suffer from wear and tear due to continuous friction during processing and actual use. The abrasion resistance of fibers refers to their ability to withstand external force wear. The abrasion resistance of fibers is closely related to the firmness of their textile products. The quality of abrasion resistance is an important indicator of the wearing performance of clothing fabrics. The wear resistance of fibers is related to factors such as their macromolecular structure, supramolecular structure, elongation at break, and elasticity.

The order of wear resistance of common fibers from high to low is as follows: nylon > polypropylene > vinylon > ethylene > polyester > acrylic > chloramide > wool > silk > cotton > linen > strong fiber > cupramide fiber > viscose fiber > acetate fiber > glass fiber.

3. Chemical resistance of fibers

The chemical resistance of fibers refers to their ability to resist damage from various chemical substances.

During the textile dyeing and finishing process, fibers come into contact with water, acids, alkalis, salts and other chemical substances to varying degrees. Meanwhile, fiber products also come into contact with various chemicals during use, such as detergents and finishing agents. Therefore, as textile fibers, they must possess certain chemical resistance to meet the requirements of textile dyeing and finishing processing as well as product usage. Furthermore, only by understanding the chemical resistance of various textile fibers can one reasonably select appropriate processing conditions and correctly use various fiber products. Among various textile fibers, cellulose fibers have a relatively strong resistance to alkali but a very weak resistance to acid. The chemical resistance of protein fibers is different from that of cellulose fibers. They are more resistant to acids than to alkalis. Protein fibers will be damaged to varying degrees in both strong and weak alkalis, and may even decompose. The chemical resistance of synthetic fibers is stronger than that of natural fibers. For instance, polypropylene and chloramide both have excellent acid and alkali resistance.

4. The linear density and length of fibers and yarns

The linear density of a fiber refers to the fineness of the fiber, and the length of a fiber refers to the length of the fiber. Textile fibers must have a certain linear density and length in order to interlock with each other and be spun into yarn relying on the frictional force between the fibers. Therefore, textile fibers have a certain linear density and length, which is one of the necessary conditions for textile processing and endowing products with practical value.

The linear density of textile fibers is closely related to the textile processing and the properties of the yarns and fabrics produced. Under normal circumstances, a lower linear density and better uniformity of fibers are conducive to textile processing and product quality. Among the influences of fiber linear density on the wearing performance of fabrics, fabrics made from finer fibers are softer. It has a relatively soft luster and can be made into thinner and lighter fabrics with finer fibers. It can also be used to produce clothing fabrics with good breathability and silk-like effects, but fabrics made of fine fibers are prone to pilling and fuzzing. Coarse-fiber fabrics can be used to make stiff, rough and thick fabrics. Similarly, the length of textile fibers is also most closely related to the quality of textiles and products. Longer fiber length, good uniformity of length and low content of short fibers are beneficial to textile processing and product quality. Under the same conditions, if the fibers are longer, the yarn strength will be higher, the yarn shedding will be uniform, the surface of the yarn will be smooth, and the fabric made from it will have good fastness, a smooth appearance, and be less prone to pilling and fuzzing. In addition, under the premise of ensuring a certain yarn quality, the longer the fiber, the finer the yarn that can be spun, which can be used to manufacture relatively light and thin fabrics. For shorter ones, length is more important than linear density. For instance, in the grading and pricing of cotton, length is the most crucial indicator.

Among textile fibers, the linear density and length of natural fibers are not uniform, and sometimes the differences are quite significant, varying with different fiber types, growth conditions, etc. In contrast, chemical fibers are artificially manufactured, and their linear density and length can be controlled and determined within a certain range according to the requirements of fiber processing and use. Puffed yarn is first spun from two fibers with different shrinkage rates into yarn, and then the yarn is treated in steam, hot air or boiling water. At this time, the fiber with a higher shrinkage rate shrinks more and is located at the center of the yarn, while the low-shrinkage fibers mixed together, due to their smaller shrinkage, are squeezed onto the surface of the yarn to form a ring shape, thus obtaining fluffy, full and elastic puffed yarn.

Linear density is one of the important physical properties and geometric features of fibers. It not only affects textile processing and product quality, but is also closely related to the wearing performance of fabrics. Similarly, linear density is also the most important indicator of yarn. The linear density of yarn affects the physical and mechanical properties, hand feel, style, etc. of textiles, and it is also one of the important bases for fabric design.

The linear density of fibers and yarns can be expressed in various forms. Generally, indirect indicators proportional to the cross-sectional area of the yarn are used to represent it. Commonly used indicators include Tex (number), metric count, imperial count, denier, etc.

5. Characteristics of common fibers

Natural fibers:

COTTON: Absorbs sweat, soft.

LINEN: It wrinkles easily, is stiff and breathable after finishing, and is relatively expensive.

RAMIE: It is a type of linen material with relatively coarse yarns. It is usually used for curtain fabrics or sofa fabrics. If it is used for clothing, it is usually mixed with linen.

WOOL: Wool yarn is relatively fine and less prone to pilling.

LAMRSWOO (small wool) : The yarn is relatively thick and is usually mixed with ANCYLIC (polyacrylonitrile fiber) to prevent clothes from deforming easily.

MOHAIR: It has a fluffy texture and is relatively warm.

Youdaoplaceholder0 (Kashmir mountain wool CASHMERE) : The fibers are fine, light and soft, and the touch is comfortable.

ANGOLA (Angora mountain wool or rabbit wool) : The yarn is fine, loose, smooth to the touch, elastic, and relatively expensive.

SILK: Soft, with a beautiful luster and high water absorption.

(2) Chemical fibers:

RAYON (artificial silk) : It is very light and soft, and is often used in COLLECTION shirts.

POLYESTER (polyester fiber) : Similar to rayon, it is easy to handle, does not wrinkle easily after ironing, and is inexpensive.

SPANDEX (stretchy nylon) : It is inherently elastic. In most fabrics mixed with cotton, only 5% to 10% of it is needed to have considerable elasticity, making clothes less prone to deformation and fading. However, it is relatively expensive

NYLON: Completely impermeable, with a relatively hard hand feel, it is suitable for windbreaker outerwear. When mixed with wool, it makes the garment stiffer.