Toprak, TubaAniş, Pervin2024-07-042024-07-042020-05-210040-5175https://doi.org/10.1177/0040517520922946https://journals.sagepub.com/doi/10.1177/0040517520922946https://hdl.handle.net/11452/42888Polyester is the most used of the synthetic fibers used in the textile industry. Nonetheless, due to its structure, the use of only disperse dyes for dyeing creates a significant weakness in its coloring. In this paper, the utilization of reactive and acid dyes in the dyeing of polyester after chemical modification with guanidine-based polymer is investigated. The dyeing of poly(ethylene terephthalate) (PET) fabrics with reactive and acid dyes was succeeded via modification with guanidine-based polymer. The effects of this polymer on disperse dyeing were also investigated. The effect of various parameters such as temperature, duration, pH, different amounts of salt and alkaline, the different dyes and processes were investigated for modifying and dyeing PET. The optimum parameters for reactive dyeing were found to be modification and dyeing in the same bath at 100 degrees C for 60 minutes without salt and alkaline, for which the obtained color strength (12.87) was higher than that of conventional disperse dyeing with carrier (10.43). In addition, polymer modification at 130 degrees C for 60 minutes before disperse dyeing provided higher color depth (24.39) than dyeing of PET by the conventional disperse high temperature method (22.48). Color fastness in laundering and the perspiration of modified and reactive dyed fabrics reached good to excellent levels (4/5). The modified and dyed samples were characterized using Scanning Electron Microscopy and Fourier Transform Infrared. Tensile tests and flexural rigidity tests for modified and reactive dyed samples were also conducted. The results indicate that the quality of the beginning material was not degraded after being modified and dyed.eninfo:eu-repo/semantics/closedAccessSurface modificationGuanidine derivativesChemical-modificationPolymeric guanidineDyeable polyesterCotton fabricsReactive dyesPet surfaceFibersWaterPoly(ethylene terephthalate)FabricChemical modificationSurface modificationGuanidineReactive dyeingScience & technologyTechnologyMaterials science, textilesArticle000534775600001265826739023-2410.1177/00405175209229461746-7748