Fiber | A Brief Description of Fiber Properties

Fiber properties: For a polymer to be considered for further development as a commercially viable fiber, it must exhibit certain physical characteristics at a comparative price. The essential physical or primary properties are those required for manufacturing or processing the fiber into yarn of fabric.

Fiber Properties are classified into 3 types. They are:

• Physical Properties
• Chemical Properties
• Thermal Properties

Physical properties

Length of width ratio: For manufacturers to able to spin a fiber into a yarn or manipulate it to produce a non-woven fabric, the fiber must be long enough to allow processing and slender enough to be flexible. A minimum length width ratio of 1000:1 is thought to be essential. Fiber shorter than 1.3 cm (1/2 inch), called short fibers, is seldom used in yarn manufacturing. Fiber length affects some yarn properties like-strength, processing, appearance etc. 

Strength: The capacity of a fiber to withstand a load is known as its strength. A fiber must possess enough strength to with stand processing by available textile machinery and provide the desire durability in its end uses. In case of a fiber, the strength is described as tenacity. The tenacity of a material is the mass stress at break, it unit being, of g/denier of g/tex. An alternative term for tenacity is specific strength, in general strong fibers produce strong fibers.

Flexibility: The ability of a fiber to resist repeated bending, folding or bowing without rupture is flexibility

Cohesiveness: With the current methods of yarn formation, staple fiber must be able to adhere to each other.  The property is known as cohesiveness or spinning quality. The surface contours of fibers directly affect cohesiveness.

Fineness: Relative size, diameter and linear density are measures of fineness of the fiber. Cotton fiber fineness express in micronaire (MIC). It means weight in micro-gram of one inch fiber. Fiber fineness affects some yarn properties like- count, yarn strength, etc.

Cross section: The cross section shape of a fiber is important because it contributes to the surface appearance of the fiber. It helps to give properties of luster, bulk and body of the fibers. yarn and fabrics. It has effect is twisting, bending etc.

Crimp: It refers to the waves or bends that take place along the length of a fiber. It increases cohesiveness and resiliency. resistance to abrasion and increased bulk or warmth or fabrics. It also helps fabric to maintain its softness or thickness, increased absorbency and show contact comfort.

Elasticity: It is the power of recovery from deformation. The fiber may be plastic or elastic depending upon the fiber condition and the surrounding environments.

Resiliency: It is the propriety of the fiber, which enables it to recover from a certain load or stretch over a period of time.
Toughness: The ability of fiber to endure large permanent deformations without rupture is called toughness.

Work of rupture: The area below the stress-strain curve provides a of the work required to break the fiber. It is commonly expressed in CN/tex

Appearance: It is judged by length, fineness, cross-section, cleanness, luster of a fiber. Generally short fibers are bulky and less lustrous.

Density: The term density means the mass per unit volume of a substance. The mass of most textile fibers is reported as density.

Elongation & Recovery
Uniformity 
Luster 
Color

Chemical properties

Water
Absorbency 
Acids
Alkalis
Heat

Thermal properties

Thermoplastic: The materials which soften or melt when exposed to heat and hardened on cooling are called thermoplastic.

Glass transition temperature (Tg): Tg is the point at which the amorphous regions of a fiber develop flow chart flow or melt, but the material remains its basic fiber form. At this temperature the materials becomes pliable, may be reformed or shaped.

Melting Point (Tm): Tm is the temperature at which the materials begins to lose its shape of form becomes molten or liquefies. Both Tg and Tm are important in the processing of thermoplastic man made fiber.

Flammability: Most textile fibers burn when exposed to a flame. Some fibers burn more readily than others. The burning characteristics used in identifying the fibers.

 

Amorphousness:
Crytallinity 
Dye Ability