Category of fibers

Fiber has two main characteristics: first, it is so fine that people cannot observe it directly with the naked eye, and the diameter is generally between a few micrometers to tens of micrometers or finer; The second reason is that its aspect ratio can reach infinity in theory, ranging from tens of thousands to tens of thousands, depending on the type of fiber. This makes the fiber exhibit long mechanical properties, such as small partial deformation during bending and torsion, and considerable deformation even within the elastic range during overall stretching. So simply put, fibers are a type of thin and long, with a diameter so small that it cannot be directly observed by the naked eye, and their length to diameter ratio is several tens of times or more.

Natural fibers

Natural fibers exist in nature and can be directly obtained. According to their sources, they can be divided into three categories: plant fibers, animal fibers, and mineral fibers.

（1） Plant fiber

Plant fiber is a natural cellulose fiber obtained from the seeds, fruits, stems, leaves, and other parts of plants. Fibers obtained from plant phloem, such as flax, jute, apocynum, etc; Fibers obtained from plant leaves, such as sisal and banana. The main chemical component of plant fiber is cellulose, so it is also known as cellulose fiber.

Plant fibers include: seed fibers, phloem fibers, leaf fibers, and fruit fibers.

Seed fiber: refers to the single-cell fibers formed by the growth of epidermal cells in some plant seeds. Like cotton and kapok.

Phloem fiber: It is a single fiber or process fiber obtained from the phloem of some plants. For example: linen, ramie, jute, bamboo fibers.

Leaf fiber: Craft fiber obtained from the leaves or leaf sheaths of some plants. For example: sisal and banana hemp.

Fruit fiber: Fiber obtained from the fruits of some plants. For example, coconut fiber.

Animal fibers

Animal fibers are fibers obtained from animal hair or insect glandular secretions. The fibers obtained from animal hair include wool, rabbit hair, camel hair, goat hair, yak hair, etc; The fibers obtained from animal gland secretions include silk, etc. The main chemical component of animal fiber is protein, so it is also known as protein fiber.

Animal fibers (natural protein fibers) include hair fibers and glandular fibers.

Hair fibers: Animal hair follicles grow into fibers composed of keratin and have a multicellular structure. For example: sheep hair, goat hair, camel hair, rabbit hair, and mare hair.

Silk fibers: fibers secreted by some insect silk glands, especially substances secreted by Lepidoptera larvae, as well as fibers formed by secretions from some mollusks. For example, silk.

Mineral fiber: It is a fiber obtained from mineral rocks with a fibrous structure, mainly composed of various oxides such as silica, alumina, magnesium oxide, etc. Its main source is various types of asbestos, such as chrysotile, crocidolite, etc.

Chemical fibers

Chemical fibers are fibers made by chemical treatment and processing. It can be divided into artificial fibers (regenerated fibers), synthetic fibers, and inorganic fibers.

Artificial fibers, also known as recycled fibers.

Artificial fibers are textile fibers made from materials containing natural fibers or protein fibers, such as wood, sugarcane, reeds, soy protein fibers, and other fiber raw materials that have lost their textile processing value, after chemical processing. The artificial fibers mainly used for textiles include viscose fibers, acetate fibers, and copper ammonia fibers.

Regenerated fibers refer to fibers made from highly purified slurries made from natural polymers, such as regenerated cellulose fibers, regenerated protein fibers, regenerated starch fibers, and regenerated synthetic fibers.

Synthetic fibers

The chemical composition of synthetic fibers is completely different from that of natural fibers. It is made by synthesizing units from substances that do not contain cellulose or protein themselves, such as petroleum, coal, natural gas, limestone, or agricultural by-products, and then using chemical synthesis and mechanical processing methods to make fibers. Such as polyester fibers (polyester), polyamide fibers (nylon or nylon), polyvinyl alcohol fibers (vinylon), polyacrylonitrile fibers (acrylic), polypropylene fibers (polypropylene), polyvinyl chloride fibers (chloroprene), etc.

Inorganic fibers

Inorganic fibers are made from natural inorganic substances or high polymer fibers containing carbon as raw materials, which are artificially drawn or directly carbonized. Including glass fiber, metal fiber, and carbon fiber.