【作者】 傅忠君；

【导师】 郑化；

【作者基本信息】 武汉理工大学 ， 材料学， 2008， 博士

【摘要】 通过研究聚乳酸纤维织物染色性能,探讨染色机理,提出染料在纤维上形成坏柱式染料扩散浓度梯度假设,应用菲克第二定律推出染色动力学数学模型及具有物理意义的K和M参数,可直观地反映染料亲和力和扩散系数;研究影响染料上染速率温度、pH值、电解质浓度、助剂等因素影响。研究了分散染料的溶解度,测定了染液吸光度变化,对照标准曲线测出待测样品染料溶液浓度,计算了染料C.I.分散红74等16种染料染液的上染百分率。对分散染料的分散稳定因素作了系列化研究。测定了染料颗粒重量平均粒径Dw,重量比表面积Sw。通过研究加入助剂前后染料分散稳定性,证明助剂对分散染料染色具有增溶稳定作用。通过研究聚乳酸纤维/棉混纺漂白处理工艺技术,制定了分散染料染聚乳酸纤维及混纺面料染色工艺曲线,确定并优化了染色前处理、染色及还原清洗工艺。研究了退煮漂一浴一步法对聚乳酸/棉混纺织物进行染前处理工艺条件。应用JL9200激光粒度仪,测试进口Dytar Dianix嫩黄XF染料平均粒径约为0.85μm,染料颗粒粒径分布服从正态分布,粒径平均小于0.98μm的染料颗粒约占85%。对比三种国产染料的粒径测试发现都在1.6μm以上,累积平均粒径基本在Dav=8-10μm之间,是进口染料9倍,且分布不均匀。通过研究分散染料粒径与染色性能关系,选取了球磨工艺条件:得到均匀稳定分散染料液体。用研磨改进细度后染料染色,上色率平均提高10%以上。通过DSC分析,经过实验测试所选聚乳酸纤维玻璃化转变温度为71.30℃左右,在161.21℃与168.68℃处分别存在较大吸收峰,说明在纤维内部存在两种结晶状态。所选C.I.分散蓝56对聚乳酸纤维的上色率最低,C.I.分散红74上色出现了上色率先降低后上升,再降低的过程。差热分析显示聚乳酸纤维耐热性较差,温度接近158℃时发生熔融,在染色后加工时需避免高温处理,以防纤维性能损伤。通过研究C.I.分散红74对PLA纤维染色上染百分率、半染时间、表观扩散系数影响,验证了用Hill公式计算与试验结果一致性;研究PLA纤维在助剂影响下染色热力学和动力学;测定了染料对聚乳酸在不同染色时间下的扩散系数D,绘制了染色速率曲线和吸附等温线;在不同染色条件下研究PLA纤维染色热力学参数,测得了PLA纤维的有效吸附体积,计算了染色亲和力、染色热和染色熵。更多还原

【Abstract】 A pillar-like diffusion model was proposed by studying the dyeing performance and mechanism of PLA fibers.A dyeing dynamics model was build up by using Fick’s second law and two parameters,K and M,of this model were related to dyeing affinity and diffusion coefficient,respectively.Effects of dyeing conditions, such as dying rate,temperature,pH,electrolyte concentration and the auxiliaries,on dyeing performance was also investigated intensively.Linear Beer-Lambert relationship was established and the dye concentration was determined by spectrophotometer.The dyeing uptake ratios of 16 different dyes, such as C.I.Disperse Red 74,were also determined.Factors influencing the stability of disperse dye were also investigated systematically.Weight average particle size, Dw,and weight specific surface area,Sw,were measured.The dispersing stability of dyes in the presence or absence of auxiliaries was studied,showing that auxiliaries can promote the dispersing stability of dyes.The technological process of dyeing PLA and its blended fabrics with disperse dyes was developed by studying bleaching process of PLA/cotton blended fabric. Process conditions such as pretreatment,dyeing and reduction were also optimized. One-step and one-bath approach was applied to pretreat the fabrics.The particle size of Dytar Dianix Yellow XF dye was determined by using JL9200 laser particle size instrument.Results showed that average particle size is about 0.85μm and particle size obeys normal distribution.85%of dye particles are of size smaller than 0.98μm.By contrast,the particle size of three domestic dyes are found to be larger than 1.6μm and the cumulative average particle size is basically between Dav=8-10μm,which is 9 times of imported dyes.An homogeneous and stable disperse dye solution can be obtained by grinding the dye beforehand.The ratio of dye uptake can be increased by 10%after grinding dyes.The glass transition temperature of PLA fiber was determined to be 71.30℃by DSC thermal analysis.As shown in DSC curve,there are two large absorption peaks at 161.21℃and 168.68℃,suggesting the existence of two crystal phases in the fiber.CI Disperse Blue 56 has the lowest dye uptake ratio and the dye uptake ratio of C.I Disperse Red 74 follows the fall-rise-fall trend.DSC analysis also showed that PLA fiber has poor thermal stability,melted at about 158℃.As a result,it is necessary to avoid high temperature treatment in dyeing PLA fiber,preventing the deterioration of the fiber.The dye uptake ratio,half-dyeing time and diffusion coefficient of C.I disperse Red 74 on PLA fiber were determined.The results were validated by the Hill equation.The dyeing thermodynamics and dynamics on PLA fiber were investigated in the presence of auxiliary.The diffusion coefficient D of dyes on PLA fiber was measured at different times of dyeing process.The dyeing-rate curves and adsorption isotherm were plotted.The PLA dyeing thermodynamics parameters were studied at the different dyeing conditions,so their effective adsorption volume was measured and their dyeing affinity,heat and entropy were calculated.更多还原