Polyester fabric is a kind of fabric that is common in clothing and life. But what are the specifications for polyester fabric? Do you know the basic composition of polyester? Polyethylene terephthalate, molecular formula [-OC-Ph-COOCH2CH2O -]n, so also known as polyester fiber (PET), its long-chain molecule has a chemical structure of H(OCH2CCOCO)NOCH2CH2OH, and the relative molecular weight is generally around 18,000-25,000.
In fact, there are still a small amount of monomers and oligomers present. These oligomers have a low degree of polymerization and are present in a cyclic form.
Polyethylene terephthalate can be obtained by polycondensation of terephthalic acid (PTA) and ethylene glycol (EG) by direct esterification to obtain ethylene terephthalate 9BHET).
1. Heat-resistant polyester is produced by melt spinning, and the formed fiber can be further heated and melted, which is a thermoplastic fiber.
Polyester has a higher melting point and a smaller specific heat capacity and thermal conductivity, so the heat resistance and heat insulation of the polyester fiber are higher. It is the best among synthetic fibers.
2. Good elasticity. The elasticity is close to that of wool, and when it is stretched by 5% to 6%, it can be almost completely recovered. The wrinkle resistance is superior to other fibers, that is, the fabric is not wrinkled, and the dimensional stability is good.
The modulus of elasticity is 22 to 141 cN/dtex, which is 2 to 3 times higher than that of nylon. Polyester fabric has high strength and elastic recovery, so it is durable, wrinkle-free and non-iron.
3. Good thermoplasticity and poor resistance to melting. Polyester is the most heat-resistant fabric in synthetic fabrics due to its smooth surface and tight internal molecules. It is thermoplastic and can be made into pleated skirts with long pleats.
At the same time, the polyester fabric has poor resistance to melting, and it is easy to form holes in the case of soot or Mars. Therefore, wear should avoid contact with cigarette butts, sparks, etc.