Polyethylene terephthalate (PET) is the most common synthetic polymer used in the textile sector by virtue of its unique superior performance attributes. However, the comfort characteristics of PET fabrics, such as their inadequate sweat-absorbing capability, low affinity for most dyestuff classes, and susceptibility to the accumulation of electrostatic charge, make them unfavorable compared to natural fibers. Rendering PET fabrics with hydrophilic and antistatic properties is difficult due to the lack of reactive functional groups. Herein, a long-lasting eco-friendly strategy to impart some desirable properties to PET fabrics was developed. The PET fabric was saponified in an aqueous caustic soda solution, followed by treatment with an amino acid, namely lysine, aspartic acid, serine, tyrosine, or cysteine, as a coupling agent, and eventually, the fabric was finished with the protein biopolymer gelatin using the pad-dry-cure method. The effects of treatment of PET fabric with the aforementioned reagents on its surface hydrophilicity, roughness, antistatic, thermal stability, ultraviolet protection, air permeability, yellowness, bending stiffness, and tensile properties were monitored. The discrepancy between the chemical structures of the untreated and finished fabrics was determined using Fourier transform infrared spectroscopy as well as by determining the carboxylic and nitrogen contents. The morphological and crystal structures of the treated fabrics were examined using scanning electron microscopy and X-ray diffraction pattern, respectively. The results indicate that a maximum add-on was obtained upon treatment of the saponified PET fabrics with 0.5 M lysine followed by 7.5% (on the weight of the fiber) gelatin using the pad-dry-cure method.The finished PET fabrics exhibited improved hydrophilic and antistatic properties with adequate protection against UV rays.Ingeneral, treatment of PET fabrics with gelatin, using a bi-functional amino acid as a coupling agent, is an effective and durable method to improve some performance and comfort features of PET fabric without having a remarkable negative effect on the fabric’s mechanical properties.
