Research On Ecological Dyeing Of Polyester Fabric Via Photografting

2-methyl-3-buten-2-ol was used to modify the reactive vinyl sulfone dye in order to prepare the modified dye monomer. The polyester fabric was modified with alkali, KH-570, GP-108and KH-570/GP-108, respectively.The modified dye monomer was photografted onto the unmodified polyester, alkali modified polyester, KH-570modified polyester, GP-108modified polyester and KH-570/GP-108modified polyester via UV irradiation. The modified dye, photograft dyed unmodified polyester, alkali modified polyester, photograft dyed alkali modified polyester, KH-570modified polyester, photograft dyed KH-570modified polyester, GP-108modified polyester, photograft dyed GP-108modified polyester, KH-570/GP-108modified polyester, photograft dyed KH-570/GP-108modified polyester were characterized by fourier transform infrared spectra(FTIR), nuclear magnetic resonance hydrogen spectral(HNMR) and scanning electron microscope (SEM).The effects of pH value, reaction time, reaction temperature, the molar ratio of the dye and monomer on modified dye were studied. The optimum process of alkali modify polyester was studied by orthogonal optimization and single-factor analysis. The effects of the volume fraction of silane coupling agent, pH value, volume ratio of ethanol and water, KH-570/GP-108ratio on modification of polyester fabric with KH-570, GP-108and KH-570/GP-108were studied. The effects of irradiation time and amount of photoinitiator on graft dying were discussed. The tensile properties, stiffness, air permeability of polyester fabrics before and after photograft dyeing were tested.The optimum conditions of dye modification were dye concentration of10g/L, reaction pH value of9, dye and monomer molar ratio of1:1.5, reaction time of60min, reaction temperature of70℃. The optimum conditions of alkali modification of polyester were NaOH concentration of40g/L, accelerant (cetyl trimethyl ammonium bromide cationic surfactant) concentration of1g/L, reaction time50min, reaction temperature80℃.The ideal conditions of silane modification of polyester with KH-570and GP-108were coupling volume fraction of2%, the reaction pH value of4, hydrolysis time of10min, coupling temperature of80℃, ethanol and water volume ratio of9:1. The optimal conditions of KH-570/GP-108modification of polyester were KH-570/GP-108volume ratio of5:5, the mixture coupling agent volume fraction of2%, the reaction pH value of4, hydrolysis time of10min, coupling temperature of80℃, ethanol and water volume ratio of9:1. The suitable photograft dyeing conditions were irradiation time of2min and initiator mass fraction of5%.New peak at1619.92cm-1appeared in the FTIR spectrum of modified dye, attributing to the stretching vibration of C=C and stretching vibration of-CH3. In the HNMR spectrum new peak of the hydrogen of the-CH3appeared at1.236ppm after modification, which proved that the dye was successfully modified. The FTIR and SEM results of photograft dyed unmodified polyester showed the modified dye was grafted onto unmodified polyester. The-CH3peak of modified dye appeared at1438.81cm-1. The SEM pictures showed that lumpy stuff was found on the surface of photografting dyed polyester fiber.SEM images showed some cavities appeared on the surface of alkali modified polyester fiber. The voids between fibers increased. The cavities of photografting dyed alkali modified polyester were not obvious, indicating that the modified dye monomer was grafted onto alkali modified polyester.The new peaks at1637.63cm-1belonging to C=C and Si-O-Si of the coupling agent were seen in the FTIR spectra. The C=C bond disappeared and the Si-O-Si still existed in the FTIR spectrum of photograft dyed KH-570modified polyester. The stripy stuff was observed in SEM pictures of photograft dyed KH-570modified polyester. Si-O-Si bending vibration was found at814.80cm-1in the FTIR spectrum of GP-108modified polyester. The modified dye graft polymer was also seen on the surface of photograft dyed GP-108modified polyester. New peaks at1637.63cm-1of C=C bond of KH-570and814.80cm-1of Si-O-Si bending vibration appeared in the FTIR spectrum of KH-570/GP-108modified polyester, either. After photografting dying, the C=C disappeared and Si-O-Si still existed, verifying photograft of modified dye onto KH-570/GP-108modified polyester.The dyeing fastness of graft dyed modified polyester was better than graft dyed unmodified polyester. The breaking strength and elongation of alkali modified polyester and graft dyed alkali modified polyester decreased, but the air permeability increased.The breaking strength, elongation, bending rigidity, work and time of rupture of silane modified polyester and graft dyed silane modified polyester mostly increased, while the permeability decreased.