The production processes used to make polyester may vary depending on the type of polyester is made:
Ethylene polyester (PET) is the most commonly-produced form of polyester fiber. The primary component of PET is petroleum-derived ethylene, and in the process of creating polyester fiber, ethylene serves as the polymer that interacts with other chemicals to create a stable fibrous compound.
There are four ways to make PET fiber, and the polyester production process varies slightly depending on which method is used:
1.Filament: Polyester filaments are continuous fibers, and these fibers produce smooth and soft fabrics.
2.Staple: Polyester staples resemble the staples used to make cotton yarn, and like cotton staples, polyester staples are usually spun into a yarn-like material.
3.Tow: Polyester tow is like polyester filament, but in polyester tow, the filaments are loosely arranged together.
4.Fiberfill: Fiberfill consists of continuous polyester filaments, but these filaments are produced specifically to have the most possible volume to make bulky products like pillows, outerwear, and stuffing for stuffed animals.
The process of creating polyester fiber begins with reacting ethylene glycol with dimethyl terephthalate at high heat. This reaction results in a monomer, which is then reacted with dimethyl terephthalate again to create a polymer.
This molten polyester polymer is extruded from the reaction chamber in long strips, and these strips are allowed to cool and dry, and then they are broken apart in to small pieces. The resulting chips are then melted again to create a honey-like substance, which is extruded through a spinneret to create fibers.
Depending on whether filaments, staple, tow, or fiberfill fibers are desired, the resulting polyester filaments may be cut or reacted with various chemicals to achieve the correct end result. In most applications, polyester fibers are spun into yarn before they are dyed or subjected to other post-production processes.