Hydrophilic Antistatic Modification: Preparation and Properties of Long-Chain Segment Copolymerized PET

To address the issue of poly(ethylene terephthalate) being highly hydrophobic and prone to static electricity due to friction, this study modifies PET through copolymerization with flexible long-chain monomers containing hydrophilic functional groups, creating a novel spinning-grade modified polyester with both hydrophilic and antistatic properties. Specifically, polyethylene glycol with a specific molecular weight (Mn = 4000) was used as a reactive hydrophilic and antistatic modification component, with a copolymerization content of 5~20%. Testing and characterization of the copolyester structure and properties showed that, compared to pure PET polyester, the introduction of hydrophilic ether bonds resulted in a significant hydrophilic modification effect, with the moisture absorption rate increasing from 0.11 to 1.12% and the surface water contact angle decreasing from 89.6° to 64.1°. Meanwhile, the volume resistivity of the copolyester decreased by 3–4 orders of magnitude compared to pure PET. This study improves the hydrophilic and antistatic properties of PET polyester through a low-cost modification method, providing essential reference for the development of functional polyesters and their fiber products.