biostudies-literatureCheng YWNational Taipei University of Technology and Chang Gung Memorial Hospital Joint Research ProgramMinistry of Science and Technology of Taiwan5487https://www.ebi.ac.uk/biostudies/studies/S-EPMC9782905biostudies-literatureUnknown14(24)Supercritical carbon dioxide dyeing (SDD) as a dyeing media not only provides a friendly dyeing environment but also significantly increases polymeric dyeing performances ascribed to strong azo dye affinity. Disperse azo dyes have shown to be highly efficient dyeing agents due to their facile coupling synthesis, side chains position, and length tunability to optimize absorption properties. Herein, we first synthesize two series of disperse red azo dyes via a coupling chemical route. Further, we investigate the position of the electron withdrawing group and alkyl chains length impact onto the absorption and color fastness properties. Upon synthesis, ¹H NMR and mass spectroscopy were used to characterize our newly synthesized series dye structure. Also, according to spectroscopic PolymersRed Disperse Azo Dye Side Chains Influence on Polyethylene Terephthalate Dyeing Performances in Supercritical Carbon Dioxide Media.PMC9782905MOST 109-2221-E-027 -114 -MY3MOST 111-2222-E-027-001NTUT-CGMH-111-04Lin SMHuang YHLee CHKuo CCChen YTCheng YWChen WWLiang FCBenas JSYu YYfalseRed Disperse Azo Dye Side Chains Influence on Polyethylene Terephthalate Dyeing Performances in Supercritical Carbon Dioxide Media.Supercritical carbon dioxide dyeing (SDD) as a dyeing media not only provides a friendly dyeing environment but also significantly increases polymeric dyeing performances ascribed to strong azo dye affinity. Disperse azo dyes have shown to be highly efficient dyeing agents due to their facile coupling synthesis, side chains position, and length tunability to optimize absorption properties. Herein, we first synthesize two series of disperse red azo dyes via a coupling chemical route. Further, we investigate the position of the electron withdrawing group and alkyl chains length impact onto the absorption and color fastness properties. Upon synthesis, ¹H NMR and mass spectroscopy were used to characterize our newly synthesized series dye structure. Also, according to spectroscopic 2022-01-01T00:00:00Z2022 Dec2025-04-04T08:00:21.014Z2025-04-04T08:00:21.014ZS-EPMC97829053655985410.3390/polym14245487