Preparation and Properties of Semi Aromatic Poly(Ester Amide)s Fibers Based on 6-Aminohexanol

The polyethylene terephthalate (PET) fiber is extensively utilized in various textiles due to its excellent mechanical properties and high modulus. However, the moisture absorption performance of PET fiber is notably inadequate, which restricts its application in high-quality fabrics. Co-polycondensation with comonomers containing hydrophilic groups has been identified as a viable approach to enhance water absorption capabilities. In this study, we aim to improve the moisture absorption performance of PET fiber by incorporating comonomer 6-aminohexanol (AH) into its main chain. The diamide diol monomer N¹, N⁴-Bis(6-hydroxyhexyl)-1,4-benzenedicarboxamide (6T6 diol) was first synthesized from AH and terephthalic acid (PTA). Subsequently, a series of poly(ester amide)s (PE6T-x), where x represents the molar ratio of amide units to ester units, were prepared through polycondensation of 6T6, ethylene glycol (EG), and PTA. The corresponding fibers were ultimately obtained via melt spinning of PE6T-x. The structures and properties of PE6T-x polymers and fibers were systematically investigated using techniques such as NMR, FT-IR, DSC, TGA, XRD, and so on. The results confirmed that the hydrophilicity and moisture absorption of PE6T-x increased with the content of 6T6; specifically, the fiber derived from PE6T-100 exhibited a moisture regain of up to 1.4 wt%, which is approximately 2.5 times greater than that of PET (0.4 wt%). This work underscores the potential for utilizing amino alcohol comonomers as an innovative strategy for enhancing the hydrophilicity of PET fabrics and provides a new idea for the application of PEAs in the field of fibers.