| The ultrasonic technology originated from the beginning of the last century. The ultrasonic wave was a kind of sound wave whose frequency was between 2×104Hz and 2×109Hz, beyond the range of the frequency that human can hear. It can cause cavitation phenominan during the propagation. The cavitation can accelerate the chemical reaction or build a new reaction path by means of special energy style.The paper studied the effects of the ultrasonic wave on the dyestuff, fiber and the process of dyeing wool with neutral dye.The kinetics and thermodynamics during the ultrasonic-dyeing process were researched when the wool was dyeing with neutral Lanacron Red S-G. The results showed that: ultrasonic-dyeing could shorten the half-time dramatically which saved by 12.20% and 39.32% on 50℃and 60℃respectively, and improve the dye uptake which rised by 11.3%, 4.2% and 5.8% on 40℃50℃and 60℃respectively in the same temperature dyeing without ultrasonic. The ultrasonic wave could augment the diffusion coefficient which rised by 22.1% 42.6% and 55.3% on 40℃50℃and 60℃respectively, decline the activation energy by 5.4% and raise the dyeing rate. It also could be found that the level dyeing property of ultrasonic-dyeing was better than dyeing without ultrasonic because of the diffusion function of the ultrasonic wave. The ultrasonic wave also could enlarge the dyestuff concentration gradient inside and outside the fiber, this would make the dyestuff diffuse faster into the interior of the fiber.The effect of the ultrasound on the dyestuff was studied by UV, Laser Particle Size Analyzer and Zeta Potential Analyzer. The results indicated that: the energy of the ultrasound could not change the color shade of the dyestuff, but it could decrease the accumulation degree of the dye stuff. The absolute value of the Zeta potential of dye solution was declined after treated by ultrasound, this was favorable for dyeing, because it reduced the repulsion force between dye anions and wool fiber.Morphology structure, chemical structure and crystalline morphology of wool fiber treated by ultrasonic wave were characterized by SEM, IR and XRD. The characterization results demonstrated that: the ultrasonic wave can partly destroy the superficial scaly structure of the wool fiber, and the destroy of the fiber that treated under 25kHz was stronger than under 40kHz. The ultrasound could not change the superficia chemical structure of the wool fiber. |
