Comparative characterization and dyeing properties of poly(ethylene terephthalate-co-polyethylene glycol) fibers and poly(ethylene terephthalate) fibers

A comparative characterization of poly(ethylene terephthalate-co-polyethylene glycol) (PCP) fibers was performed using various parameters, including chemical and supramolecular structures, thermal properties, and physical properties. Dynamic scanning calorimetry and X-ray diffraction analyses revealed that PCP exhibits a lower melting point, glass transition temperature, and crystallinity than PET. In terms of tensile properties, PCP exhibited reduced tensile strength but increased elongation at break, indicating enhanced toughness. Dyeing test results demonstrated that PCP fibers are disperse dyeable at lower temperatures and exhibited optimal dyeability at 100 °C, surpassing PET, without compromising leveling properties or color fastness. These findings underscore the potential for energy savings and process streamlining through atmospheric-pressure dyeing.