①High strength. The dry strength is 4~7cN/dex, and the wet strength decreases.
② Moderate elongation is 20%~50%.
③High modulus. Among the large variety of synthetic fibers, the initial modulus of polyester is the highest, and its value can be as high as 14~17GPa, which makes the size of the polyester fabric stable, without deformation, distortion, and lasting pleats.
④Good resilience. Its elasticity is close to wool. When it is stretched by 5%, it can be almost completely recovered after removing the load. Therefore, the crease resistance of polyester fabrics exceeds that of other fiber fabrics.
⑤ Wear resistance. Its abrasion resistance is second only to nylon, and more than other synthetic fibers, the abrasion resistance is almost the same.
3. Chemical stability. The chemical stability of polyester depends mainly on the molecular chain structure. In addition to poor alkali resistance, polyester has excellent resistance to other reagents.
① Acid resistance. Polyester is very stable to acids (especially organic acids). After immersed in a hydrochloric acid solution with a mass fraction of 5% at 100℃ for 24h, or immersed in a sulfuric acid solution with a mass fraction of 70% at 40℃ for 72h, its strength There is no loss, but it cannot resist the long-term effect of concentrated nitric acid or concentrated sulfuric acid at room temperature.
②Alkali resistance. Because the ester group on polyester macromolecule is easily hydrolyzed by alkali. The action of concentrated alkali at normal temperature and dilute alkali at high temperature can damage the fiber. Only at low temperature is it stable to dilute or weak alkali.
③ Solvent resistance. Polyester has a strong resistance to common non-polar organic solvents, even at room temperature even for polar organic solvents. For example, soaking in acetone, chloroform, toluene, trichloroethylene, carbon tetrachloride at room temperature for 24 hours, the fiber strength does not decrease. Under heating, polyester is soluble in phenol, xylenol, o-dichlorophenol, benzyl alcohol, nitro
Benzene and phenol-carbon tetrachloride, phenol-chloroform, phenol-toluene and other mixed solvents.
4. Microbial resistance. Polyester is resistant to microorganisms and is not affected by worms, molds, etc. It is not necessary to prevent insects from storing polyester clothing, and the fabric is easier to store.
