The dyeing temperature of natural dye lac red on two kinds of natural protein fibers was studied, and the interaction between dyestuff and fiber was discussed through thermodynamic study and density functional theory ...The dyeing temperature of natural dye lac red on two kinds of natural protein fibers was studied, and the interaction between dyestuff and fiber was discussed through thermodynamic study and density functional theory (DFT) calculation. The optimum temperature for lac red dyed silk was 60˚C and wool showed a better response at 90˚C. The thermodynamics study revealed good Nernst isotherm and Freundlich adsorption models respectively, and the lac dye adsorption processes were both spontaneous and exothermic. The potential interaction of Laccaic acid A with the external environment by electrostatic potential and atomic charge distribution was first explored. With molecular simulation, Laccaic acid A and glycine composed 8 stable complexes. Then, typical hydrogen bonds, bond length, and binding energy, etc. were analyzed. The results revealed lac red on silk and wool fabric mainly depended on the weak hydrogen bonds and van der Waals force which determined the low dye fastness.展开更多
The dyeing behavior of cationic dyes to acrylic fiber with self-made low temperature dyeing accelerant was investigated in this study. Compared with conventional dyeing, the acrylic yarn was dyed with Cationic Turquoi...The dyeing behavior of cationic dyes to acrylic fiber with self-made low temperature dyeing accelerant was investigated in this study. Compared with conventional dyeing, the acrylic yarn was dyed with Cationic Turquoise Blue X-GB at 85℃ in the presence of accelerant and absence of accelerant, respectively. The influence of low temperature dyeing aceelerant on the dyeing mechanism of acrylic fiber dyed with cationic dye was analyzed through kinetics and thermodynamics study. The results show that adding dyeing accelerant ran heighten the equilibrium dye-uptake, dyeing rate constants, diffusion coefficients, and shorten half-dyeing time for acrylic fiber dyed with cationic dyes. Furthermore, the partition coefficient, the standard affinity, and the dye saturation value also increased in the dyeing at 85℃.展开更多
文摘The dyeing temperature of natural dye lac red on two kinds of natural protein fibers was studied, and the interaction between dyestuff and fiber was discussed through thermodynamic study and density functional theory (DFT) calculation. The optimum temperature for lac red dyed silk was 60˚C and wool showed a better response at 90˚C. The thermodynamics study revealed good Nernst isotherm and Freundlich adsorption models respectively, and the lac dye adsorption processes were both spontaneous and exothermic. The potential interaction of Laccaic acid A with the external environment by electrostatic potential and atomic charge distribution was first explored. With molecular simulation, Laccaic acid A and glycine composed 8 stable complexes. Then, typical hydrogen bonds, bond length, and binding energy, etc. were analyzed. The results revealed lac red on silk and wool fabric mainly depended on the weak hydrogen bonds and van der Waals force which determined the low dye fastness.
基金Science and Technology Department of Zhejiang Province,China (No. 2008C01069-4)
文摘The dyeing behavior of cationic dyes to acrylic fiber with self-made low temperature dyeing accelerant was investigated in this study. Compared with conventional dyeing, the acrylic yarn was dyed with Cationic Turquoise Blue X-GB at 85℃ in the presence of accelerant and absence of accelerant, respectively. The influence of low temperature dyeing aceelerant on the dyeing mechanism of acrylic fiber dyed with cationic dye was analyzed through kinetics and thermodynamics study. The results show that adding dyeing accelerant ran heighten the equilibrium dye-uptake, dyeing rate constants, diffusion coefficients, and shorten half-dyeing time for acrylic fiber dyed with cationic dyes. Furthermore, the partition coefficient, the standard affinity, and the dye saturation value also increased in the dyeing at 85℃.
