Aminolysis of polyethylene terephthalate fabric by a method involving the gradual concentration of dilute ethylenediamine

Aminolysis of polyethylene terephthalate (PET) fibers can endow fibers high hydrophilicity and reactive NH2 groups; however, the ethylenediamine solution aminolysis method severely damages the PET fibers. In this paper, a facile aminolysis method involving the gradual concentration of dilute ethylenediamine was developed to aminate PET fibers. The results showed that the hydrophilicity of the PET fabric substantially improved and that reactive NH2 groups were introduced onto the PET fibers. The water absorption time and contact angle of the treated PET fabrics decreased to 15 s and 0°, respectively. The liquid wicking height of the treated PET fabric increased from 0.4 cm (original PET fabric) to 11.0 cm. Fourier transform infrared spectra demonstrated that NH2 groups were successfully introduced onto the PET fibers. Scanning electron microscopy showed almost no difference between the surfaces of the original and treated PET fibers. X-ray diffraction analysis indicated that the main structure of the PET fibers was well maintained. The aminated PET fabrics retained the weight loss, breaking strength and elongation, crease recovery angle, stiffness and whiteness of the original PET fabrics. The aminolysis of PET fibers via the gradual concentration of dilute ethylenediamine is a promising method for the efficient, rapid, and eco-friendly modification of PET fibers.