Polyester
History of Polyester Fiber
Polyester fiber was discovered by Dr. W.H. Carothers, an American, in 1930, who was also the discoverer of nylon fiber. Later, British scientists continued researching until they produced the first polyester fiber, named Terylene, in 1941. Then in 1946, the DuPont company purchased the rights to produce it in the United States under the name Dacron (Dacron). Polyester fiber then became widely and rapidly popular, more so than other types of synthetic fiber.
Polyester is a fiber produced from the reaction of Polymerization of Dihydric alcohol and Dicarboxylic acid, as in the example reaction using Ethylene glycol and Terephthalic acid
When these chemicals are combined in the production process for about 80-100 (Polymer repeat units), the resulting polyester can be made into fiber. The polyester obtained from the initial production process comes out as a strand and is then cut into small pieces. When it is to be made into fiber, it must be melted and pressed through a Spinnerette. The extruded fiber hardens on contact with air, and is then drawn and stretched so the fiber becomes tough and strong.
Properties of Polyester Fiber
Physical Properties of the Fiber
1. Shape
Under a microscope, the longitudinal shape has a smooth, even surface along the entire length. Small dots are often seen in the fiber, due to pigment added to reduce the fiber's shine. The cross-section is round, but some types, such as Dacron T-62, have a rounded-triangular cross-section, Vycron has an oval shape, and Trevira has a serrated shape all around.
2. Tenacity
Tenacity varies from 2.5-9.5 grams per denier. When wet, the tenacity decreases.
3. Elasticity
Has good elasticity, does not wrinkle easily, and holds its shape well.
4. Moisture Absorption
Absorbs moisture at a low rate, about 0.4-0.6% under standard conditions, and is difficult to dye. If more space is needed within the fabric (wickability), the fabric must be produced with looser yarns and a more open weave so air can pass through more easily, helping it feel more comfortable to wear.
5. Heat Resistance
Polyester melts at a temperature of 230-290°C. Heat does not cause the fiber's color to fade. Fiber that has undergone heat setting will not stretch, shrink, or wrinkle. If ironed at a temperature lower than the heat-setting temperature, the fiber will not be damaged. When burned, it produces black smoke and melts, leaving gray-black ash in the form of a hard round bead that does not break apart.
Chemical Properties of the Fiber
Polyester fiber is not resistant to strong alkalis and strong acids, which reduce the fiber's strength. If the chemical is concentrated and the temperature increases, the fiber can break. The organic substance that can dissolve the fiber is meta-cresol phenol. Polyester fiber is an Oleophilic fiber, meaning it absorbs oil well.
Biological Properties of the Fiber
Bleach, soap, and detergent do not damage the fiber. It is resistant to sunlight, and even when stored for a long time, moths, insects, and mold do not harm it.
Polyester Fiber and Its Practical Uses
Fabric produced from polyester fiber is the most popular among all synthetic fiber groups. Polyester has many trade names depending on the country and manufacturer, such as Dacron, Avlin, Encron, Kodel, Trevira, and Vycron. Polyester produced in the United States is called Terylene, that produced in England is called Tetoron, while polyester produced in Japan is called Toray.
A good property of polyester fiber is that it does not wrinkle easily, is comfortable to wear, and is easy to care for — it is a Wash and Wear type fiber. Besides being produced as fabric from polyester fiber alone, polyester fiber is also commonly blended with other types of fiber, such as rayon, silk, cotton, linen, and wool, usually making up no less than 60% of the blend, for example, 65% polyester and 35% cotton.
Blending polyester fiber with other types of fiber is done so that the fabric obtained from the blend has improved properties in terms of beauty, durability, and suitability for practical use. Manufacturers of fabric from polyester fiber, and of fabric produced from blended fiber containing polyester fiber, can produce everything from lightweight fabric to thick fabric used for making shirts, skirts, pants, and suits, among other things.
Cleaning can be done by either wet washing or dry cleaning. It can be used with detergent, soap, and any type of bleach. If washed with water, it should not be wrung to dry; instead, the water should be shaken out, and it should be dried in the shade or in mild sunlight. Ironing is not necessary. If stained with grease, the stain should first be treated with shampoo before washing normally, which will make the stain easier to remove.
General Properties of the Polyester Fiber Group
In summary, the good and bad properties are as follows:
1. Good elasticity, does not wrinkle easily
2. Difficult to dye, low moisture absorption
3. Holds its shape and size well, even in a liquid state
4. Can be both wet washed and dry cleaned
5. Easy to wash, dries quickly
6. Sensitive to heat
7. Does not require ironing
8. Good resistance to abrasion
9. Difficult to wash out grease stains
10. Strong and durable
11. Fabric woven from staple fiber holds its shape well