The physical properties of polyester fibers

1.Color: Polyester is generally milky white with a silky finish. To produce non glossy products, a matting agent TiO2 needs to be added before spinning. To produce pure white products, a whitening agent needs to be added. To obtain colored fibers, pigments or dyes need to be added during spinning.
2.Surface and cross-sectional shape: Conventional polyester has a smooth surface and a nearly circular cross-section. If an irregular spinneret is used, fibers with special cross-sectional shapes such as triangles, Y-shaped, hollow, etc. can be made.
3.Density: When completely amorphous, the density of polyester is 1.333g/cm ³. When fully crystallized, it is 1.455g/cm ³. Usually, polyester has a high crystallinity, with a density of 1.38-1.40g/cm ³ Between, with wool (1.32g/cm) ³) Similar.
4.Moisture regain: Under standard conditions, the moisture regain of polyester is 0.4%, which is lower than that of acrylic (1%~2%) and nylon (4%). Polyester has low moisture absorption, so its strength decreases less when wet, and the fabric is not easily deformed after washing. But during processing and wearing, static electricity is severe, and the breathability and moisture absorption of the fabric are poor.
5.Thermal performance: The softening point of polyester is 230-240 ℃, the melting point is 255-265 ℃, and the decomposition point is about 300 ℃. Polyester can burn in fire, curl and melt into beads, accompanied by black smoke and a fragrant aroma.
6.Light resistance: Its light resistance is second only to acrylic fiber. The light resistance of polyester is related to its molecular structure, with a strong absorption band in the 315 nm wavelength range. Therefore, after 600 hours of sunlight exposure, the intensity loss is only 60%, similar to cotton.
7.Electrical performance: Polyester has poor conductivity due to its low moisture absorption. The dielectric constant within the range of -100 ℃ to+160 ℃ is 3.0~3.8, making it an excellent insulator.