Analysis Of Spandex Fiber Characteristics

Spandex fiber

It is a synthetic fiber with high elongation at break (400%), low modulus and high resilience. It has high elongation (500 - 700%), low elastic modulus (200% elongation, 0.04 - 0.12 g / D) and high resilience (200% elongation, 95 99%).

In addition to higher strength, other physical and mechanical properties are very similar to natural latex fibers.

It is more resistant to chemical degradation than latex yarn, and has moderate thermal stability. The softening temperature is above 200 c.

Most dyes and finishing agents for synthetic fibers and natural fibers are also suitable for dyeing and finishing spandex.

Spandex is resistant to sweat, seawater and various dry cleaners and most sunscreen.

Long term exposure to sunlight or bleaching agents will also fade, but the degree of fading varies with the type of spandex.

The biggest advantage of spandex fabric is good elasticity, it can stretch 5-8 times, no aging, spandex can not be woven individually, usually woven with other raw materials, spandex ratio is between 3 and 10%, and swimsuit fabric spandex ratio reaches 20%.

Supplement:

Kapok fiber is a kind of fiber attached to fruit and pod in several species of kapok, Kone, and belongs to unicellular fiber, which is the same as cotton fiber.

But cotton fiber is

1. The basic properties of kapok fiber

1. Physical properties

Kapok fiber has three kinds: white, yellow and yellow brown. The length of the fiber is about 8 - 32mm, and its diameter is about 20-45 m.

The longitudinal appearance is cylindrical, with smooth surface and no obvious turning. The middle part is thicker, the root ends are blunt, the ends are thin, and the ends are closed.

A large hollow tube wall with a circular cross-section or ellipse, with a hollow degree of up to 80 - 90%, and a cross-section of cells without balloon rupture.

The unique fiber structure of kapok fiber also determines its basic properties different from other natural fibers.

Kapok fiber has a high degree of hollowness and thin cell walls, so its relative density is small and buoyancy is good.

The fiber can withstand 20-36 times load in the water without sinking. The relative torsion rigidity of kapok fiber is 71.5 * 10-4eN. Em2. Tex-2, larger than that of glass fiber, which will cause the twisting efficiency to decrease.

The moisture regain of kapok fiber can reach 10.73%, which is equivalent to 10.6% of that of mercerized cotton.

The average refractive index of kapok fiber is 1.71761, which is slightly higher than that of cotton, which causes the glossy bright and smooth circular section of kapok fiber, which increases the glossiness of the cotton fabric. The average refractive index is about 1.59614.

2, chemical properties

Kapok fiber contains about 64% cellulose, accounting for 13% of lignin, and also contains 8.6% moisture, 1.4 - 3.5% ash, 4.7 - 9.7% water soluble substances and 2.3 - 2.5% xylan and 0.8% waxes.

Kapok fiber has good chemical properties and good acid resistance. At room temperature, dilute acid has no effect on it, and the alkali resistance of kapok fiber is good. Sodium hydroxide has no effect on Kapok at room temperature.

Kapok fibers can be dyed by direct dyes. However, because kapok fibers contain a large number of lignin and hemicellulose, they are entangled with cellulose and intermolecular forces, resulting in the partial hydroxyl of cellulose fibers are blocked and entangled, resulting in dye molecules can not enter smoothly, so that the dye uptake is only 63%.

Two. Application of kapok fiber

1, medium and high grade garments, home textile fabrics

Kapok fibers have poor spinnability and are generally difficult to spin.

It can be used to blend fabrics with cotton, viscose or other cellulose fibers, and can make fabrics with gloss and good feel.

2, medium and high grade bedding, pillow core, cushion and other filling materials.

Kapok fiber also has some excellent characteristics, such as moisture absorption, no entanglement, pest control and hygiene. It is very suitable for mattress and pillow core.

These characteristics are very important in wet climates or wet areas, and are good filling materials.

A large amount of static air formed by its thin wall and large hollow structure can achieve good thermal effect.

However, the compression elasticity is poor, and the bulking performance will be significantly reduced under repeated compression. This leads to the wide application of kapok fibers in these fields.

3. Buoyancy material for life preserver

The buoyancy of the new kapok aggregate has good buoyancy retention. Even if the packaging material is slightly damaged, the buoyancy damage degree is very small. After drying, the kapok aggregate will regain its buoyancy.

In 1946, the US Coast Guard conducted buoyancy tests on natural fiber assemblies such as kapok, glass fiber, cattail, milkweeds and so on. It was concluded that kapok was the best buoyancy material. In 1982, practical tests were carried out on life jackets filled with kapok and PVC, PE and other foam plastic filled lifebuoy. It was proved that the wearing of plastic foam life jackets was worn out from aging, while the kapok lifejacket did not have such a problem, which had unique advantages.

4. Heat insulation and sound absorption materials

Due to the high enthalpy, low thermal conductivity and high sound absorption efficiency of kapok fiber, it has been used as a heat insulation and sound insulation material in industry, such as the insulation layer and sound-absorbing layer of the house.