Dyeingproperties Of Reactive Dyesonramieyarninliquidamm Onia

Traditional dyeing of cellulosic fiber is the most discharge of industrial wastewater and maximal energy consumption process in printing and dyeing. The waste water of printing and dying is difficult to reduced,and has been widely regarded as the water pollution at home and abroad,which is known with very deeply chromaticity, high component of organic harmful chemical compounds, and other performances. While the liquid ammonia staining would heavily reduce the pollution of water and the energy consumption. This paper researches the low exhaustion rate and poor levelness problem in the dyeing technology of liquid ammonia, take liquid ammonia dyeing of ramie yarn as a research object,discusses the sorption and diffusion process of ramie yarn with five sorts of reactive dyes in diverse dyeing conditions, determine the dyeing process. Finally, discuss the dyeing properties of reactive dyes on ramie yarn in liquid ammonia.Cationic ramie yarn was prepared with 2, 3-epoxypropytrimethylammonium chloride agent. Subsequently, the dyeing of original and cationic ramie yarns in liquid ammonia with the five kinds of reactive dyes or dyeing time varied from 10 to 600 s with 10% dye o.m.f and dyeing concentration ranged from 1 to 100% dye o.m.f for 600 s dyeing time at-35℃ at a liquor ratio of 35:1 was evaluated. After dyeing, the samples were baked at 100℃for 10 min. So as to discussion the liquid ammonia mercerization, the unmodified ramie yarns are taken in the liquid ammonia under the temperature of-35℃,and removing the yarns at the different time period, then, baking at 100℃ for 10 min.The results show that the cationic treatment increased the dye exhaustion and fixation, and ameliorated the wash fastness, but decreased the rubbing staining degree. The exhaustion percentages of both original and cationic ramie yarn were increased with the increasing of dyeing time, and the equilibrium was reached at 60 s and 180 s, which were with 21% and 34% of exhaustion percentage, to the original and cationic ramie yarns respectively. The fixation values of original ramie were between 40-76%, while the cationic ones were approaching to 100%. In the variable of dye o.m.f, the exhaustion percentage of both samples decreased with the increase of dye mass. The fixation values of original ramie yarn were fluctuated in the range of 25-34%; compere with original one, the cationic sample decreased to 85% at 100% o.m.f from 100% at 50% o.m.f. However, for the dye adsorption capacity unit of mass,both samples were linearly raised with augmenting of dye o.m.f.The adsorption process of the liquid ammonia dyeing followed the second-order kinetics. The Langmuir and Freundlich adsorption models were fitted to depict the experimental isotherms. The experimental data of dyeing untreated ramie was acceptable to the Freundlich model, while cationic ramie fitted the Langmuir isotherm.After silkier of the liquid ammonia, the fiber breaking strength raised, the fiber gained little damage became more smooth, the yarn prickle turned weakening, the fiber wear ability enhanced, in general, the mercerizing effect is better.