乙醇/水体系中改性蚕丝织物的活性染料染色动力学和热力学

Kinetic and thermodynamic of reactive dye study on silk fabric modification in ethanol/water system

为进一步提升蚕丝织物的染色深度,利用活性红3BS在乙醇/水体系中对经阳离子表面活性剂改性的蚕丝织物进行染色,分析了染色温度、pH值、染料用量和染色时间对改性蚕丝织物性能的影响,同时也探究了改性蚕丝织物在乙醇/水体系中的动力学和热力学机制。试验结果表明:染色温度是影响改性蚕丝织物K/S值、明暗值、红绿值、黄蓝值和总色差值最大的因素,且随着染色温度的升高,染色速率常数先增大后降低,饱和吸附量逐渐增大,而半染时间、染料分配系数和标准亲和力逐渐减小;改性蚕丝织物的染色焓为-28.693 kJ/mol,染色熵为-0.066 kJ/(℃·mol),改性蚕丝织物在乙醇/水中的染色过程为放热反应;改性后的蚕丝织物染色深度有所提升,各项染色牢度基本未发生变化。

In order to further improve the dyeing depth of silk,on the dyeing of cationic surfactant-modified silk in the ethanol/water system by Reactive Red 3BS was reported.The effects of temperature,pH value,material ratio(o.w.f)and time on the modified silk were analyzed.The kinetics and thermodynamic mechanisms of the modified silk in the ethanol/water system were explored.The experimental results show that the temperature is the factor influencing the K/S value,the light and dark value,the red and green value,the yellow and blue value and the total color difference of the modified silk.As the temperature increase,the dyeing rate constant demonstrates an increase and then decreased afterwards.The saturated adsorption amount,partition coefficient and standard affinity gradually increases while the half dyeing time gradually decreases.The dyeing enthalpy is-28.693 kJ/mol,and the dyeing entropy of the modified silk is-0.066 kJ/(℃·mol),indicating that the dyeing process of the modified silk in ethanol/water is exothermic.It is noted that although the dyed depth of the modified silk was improved,the dyeing fastness shows no substantially change.