Polyester fibers, the synthetic fibers, are long chain polymers derived from coal, air, water, and petroleum. They are formed through chemical reaction between an acid and alcohol. In this reaction, two or more molecules combine to make a large molecule whose structure repeats throughout its length. These molecules are very stable and strong. There are variations in the compositions and therefore in the properties of polyester fibers.
Types of Polyester
The polyester fibers are generally available in two varieties- PET (polyethylene terephthalate) and PCDT (poly-1, 4-cyclohexylene-dimethylene terephthalate). PET is the most common production. It is stronger than PCDT, while PCDT has more elasticity and resilience. PET can be used alone or blended with other fabrics for making wrinkle free and stain resistant clothing that can retain its shape. PCDT is more suitable for heavier applications, such as draperies and furniture coverings. Modifications can be introduced in each of these varieties for obtaining specific properties.
For manufacturing PET Polyester, the main raw material is ethylene derived from petroleum. It is oxidized to produce a glycol monomer dihydric alcohol which is further combined with another monomer, terephthalic acid at a high temperature in a vacuum. Polymerization, the chemical process that produces the finished polyester, is done with the help of catalysts. The colorless molten polyester then flows from a slot in a vessel on to a casting wheel and takes shape of a ribbon as it cools to hardness. The polymer thus produced is then cut into very small chips, dried to remove all moisture and blended to make it uniform for getting it ready for spinning into yarn. PCDT Polyester
This variation of polyester is made by condensing terephthalic acid with 1, 4-cyclohexane-dimethanol to form poly-1, 4-cyclohexylene-dimethylene terephthalate or the PCDT Polyester. As for PET Polyester, PCDT is...