1.What is fiber?
Fiber: Important fiber properties are describe in this article. The word fiber or fiber comes from the Latin word fibra. Fiber or fiber is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The most robust engineering materials often incorporate fibers, for example, carbon fiber and ultra-high molecular weight polyethylene. But all fiber is not textile fiber. To be textile fiber, fiber has some special properties. Textile fibers are materials of natural or artificial origin that can be converted into yarn and fabric for clothing and domestic and industrial purposes by interlacing or interloping. In other words, textile fiber is a class of natural or manufactured materials with some special properties, i.e., spin ability or spun-able, high length-to-width ratio, sufficient strength, flexibility, dyeing ability, and cohesiveness, stiffness, ability to resist, good elongation properties.
2. Fiber Properties:
The properties of textile fiber may classify into three kinds. Such as:
- Physical properties.
- Chemical properties.
- Mechanical properties.
2.1 Physical Properties:
The physical properties are mentioned below are worth considerable for a textile fibers.
- Length of fiber(Cm/Inch)
- Tenacity/specific length. (Gram/Denier)
- Fineness of the textile fiber.(mic-value)
- Specific gravity.(G/cc)
- Elastic recovery(%)
- Swelling and water retention (%)
- Glass transaction temperature(Tg)
- Specific heat
- Pilling behavior.
- Limiting oxygen index(LOI)
- Moisture regain(%) and Moisture content(%)
- Fibre breaking length.
- Fiber maturity(%)
- Crystalline melting point(Tm)
- Thermal conductivity
2.2 Chemical Properties:
- Solubility in organic salt.
- Solubility in aqueous salt.
2.3 Mechanical Properties:
3. Important Fiber Properties:
Some important properties of cotton is describe below:
3.1 Length of Fiber:
The length of fiber is the essential property of fiber. The length of the fiber must be considerably more significant than the diameter. The fiber producer sells fibers as a staple, filament, or filament tow. Staple fibers are short fibers measured in cm or inch. The length of the natural fiber, except for silk, are mostly some millimeter up to server cm long. The length ranges from 2 to 46 cm or 3/4 inch to 18 inches. On the other hand, man-made fibers are filaments form. Filaments are long and continuous fiber strands of indefinite length. Generally, filaments are measured in miles or km. Filaments may be either monofilament, where only one filament is used, or multi-filament, where more filaments are used. Another form of fiber length is filament tow. Filament tow, produced as a loose rope of several thousand fibers, is crimped or textured and cut to staple length.
Tenacity is the second necessary property of textile fiber. Tenacity, or tensile strength, is the ability of a fiber to withstand a pulling force. Tenacity is measured by securing both ends of the fiber in clamps and measuring the force needed to break or rupture the fiber. Breaking tenacity for a fiber is the force, in grams per denier or tex, required to break the fiber. A fiber’s strength depends on the length of the polymer chain. The degree of orientation of these polymer chains, the strength, and types of the forces of attraction between the polymer chains. The longer a polymer chain is, the higher the degrees of orientation and crystallization. The tenacity of glass fiber is the highest of all other fibers. The tenacity of glass fiber is about 9.6/6.7 gm/denier. The tenacity of acetate is the lowest of all other fibers. The tenacity of acetate fiber is about 1.2-1.4 gm/denier. Cotton fiber has widely used all world. The tenacity of cotton fiber is about 3.5-4.00 gm/denier.
We can provide measurement of fiber by the following law:
3.3 Fineness of fiber:
Fiber fineness usually is one of the three most important characteristics. The fineness of fiber is defined in many ways. A multitude of fibers in the cross-section provides high strength and better distribution in the yarn. The fiber fineness determines how many fibers are present in a cross-section of yarn of a given thickness. Additional fibers in the cross-section provide additional strength and better evenness in the yarn. About 30 fibers are required at the minimum in the yarn cross-section, but there are usually over 100. One hundred is approximately the lower limit for almost all new spinning processes. This indicates that fineness will become still more important in the future. For yarns and fibers, fineness is usually measured by the ratio of mass to length.
For man-made fiber dtex is used.
3.4 Specific Gravity:
Specific gravity is a measure of fiber weight per unit volume. Lower-density fibers can be made into the thick fabric that is more comfortable than high-density fibers made into heavy fabrics. It is usually expressed in grams per cubic centimeter. The specific gravity of cotton fiber is 1.50-1.55 g/cm3. The specific gravity of polyester fiber is 0.4 g/cm3, the lowest specific gravity of all other fibers.
3.5 Elastic recovery and elongation:
When a fiber is subjected to a small force, it may exhibit almost perfect elasticity. Elasticity is the property of a fiber to recover its original length after stretching caused by a load. The elastic recovery of textile fiber means the ability of a fiber to return to its original dimension after applying load. It is measured as the percentage of return to the actual length. Elastic recovery varies with the amount of elongation and with the length of time the fabric is stretched. Fibers with poor elastic recovery tend to produce fabrics that stretch out of shape. Fibers with good elastic recovery tend to produce fabrics that maintain their shape. Conversely, elongation refers to the degree to which a fiber may be stretched without breaking. It is measured as percent elongation at the break by measuring the change in length and comparing that to the original length.
3.6 Moisture regain and moisture content:
A textile product should be comfortable when it is worn or used. Comfortable of fabric depends on the absorbency of fiber. Absorbency is the ability of a fiber to take up moisture from the body or from the environment. It is measured as moisture regain, where the moisture in materials is expressed as a percentage of the weight of the moisture-free materials. The term of regain is used for moisture absorption in a fiber. This is the amount of moisture present in textile materials expressed as the percentage of the oven dry weight of the textile. This dry mass is the constant weight of the textile obtained after drying at a temperature of 1050 C to 1100 C. on the other hand, the moisture content is the mass of moisture in fiber and is expressed as a percentage of the total weight. It measures the amount of water held under any particular set of circumstances. The moisture content is always lower than the regain.
This characteristic refers to the ability of the fiber to stick together in yarn manufacturing processes. Cohesiveness indicates that fibers tend to hold together during yarn manufacturing due to the longitudinal contour of the fiber or the cross-section shape that enables the fiber to fit together and entangle sufficiently to adhere to one another.
Resiliency is the ability of a fiber to return to its original shape after bending, twisting, or crushing. Resilient fibers usually produce resilient fabrics. An easy test for resiliency is to crunch a fabric in your hand and watch how it responds when your open your hand. Resilience is the property of a fiber that enables it to recover from a particular load or stretched position.
3.9 Thermal retention:
Thermal retention is the ability of a fiber to hold heat. Because people want to be comfortable regardless of the weather. A low level of thermal retention is favored in hot weather, and a high level in cold weather. The property is affected by fiber, yarn, fabric structure, and fabric layering of fabrics.
The uniformity of fiber is one of the most important properties of the fiber. The regularity of the final yarn depends on fiber uniformity. To minimize the irregularity in the final yarn, the fibers must be similar in length and width, i.e., be uniform. The inherent variability in the natural fiber can be averaged out by blending natural fibers from many different batches to produce a uniform yarn.
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- Corbman, B. P. (1983). Textiles Fiber to Fabric. New York: Mc Graw Hill.
- Kadolph, S. J. (2009). Textiles. New Delhi: Dorling Kindersley.