Investigation of dyeing with reactive dyes on cationic dyeable polyester fabric by applying polyvinyl alcohol and ammonium salt

• The reactive dyes are applied on polyester fabric instead of disperse dyes. • The surface of the PET was modified using PVA and ammonium salt. • The dyed CDP fabric shows an excellent level of fastness properties including light fastness. • The process indicates the sustainability of dyeing for polyester fabric. In the dynamic landscape of the textile industry, the light fastness properties of cationic dyeable polyester (CDP) fabrics when subjected to basic dyes are observed to be moderately average. This study delves into the augmentation of CDP fabric surfaces through the strategic application of polyvinyl alcohol (PVA) in conjunction with ammonium salt and NaOH. The efficacy of this modification process is systematically assessed by evaluating critical parameters including color strength (K/S), exhaustion ( %), and fixation ( %). Expanding the analysis, the chemical intricacies of this process are explored via Fourier-transform infrared (FTIR) spectroscopy analysis. Furthermore, the comprehensive evaluation encompasses an assessment of fastness, bursting strength, absorbency, and wicking properties of the fabrics, revealing a satisfactory performance. Particularly noteworthy are the outcomes of samples pre-treated with 3 % PVA alongside NaOH and (NH 4 ) 2 SO 4 , which exhibit superior results compared to alternative treatments. For the specific case of 3 % PVA and NaOH pre-treatment, the violet color variant exhibits the highest exhaustion and fixation values at 27 % and 20 %, respectively, while the blue color variant attains the peak K/S value of 0.54. Notably, all samples demonstrate light fastness ratings ranging from 4 to 4–5, indicating good light fastness properties. The fundamental transformation of CDP fabric is evidenced by FTIR spectroscopy, revealing the presence of -OH groups subsequent to PVA and NaOH or (NH 4 ) 2 SO 4 pre-treatment. These functional groups play a pivotal role in the interaction with reactive dyestuffs, thereby rendering cationic dyeable polyester amenable to dye absorption.