空气变形工艺对成纱熵变的影响

 化纤长丝在变形加工，尤其是在空气变形加工过程中会发生明显的熵变现象，研究表明成纱熵变与变形纱各主要结构性能参数之间存在显著的相关性。为了查明变形工艺参数对成纱熵变的影响，针对目前较具代表性的空气变形工艺参数和异收缩变形工艺参数设计了单因子试验，主要包括单复丝规格、空气变形加工超喂率和异收缩差等。结果显示，在单丝线密度一定条件下，成纱熵变随着复丝线密度的增加而增加；在复丝线密度一定的条件下，成纱熵变随单丝线密度的增加而降低。在空气变形加工过程中，成纱熵变随丝束超喂率的增加而增加。在异收缩变形加工中，成纱熵变随着异收缩差的增大而增大。

Effects of air-texturing process on texturing entropy change

The phenomenon of entropy change was found during texturing, especially in course of air-jet texturing of the chemical filaments, further researches had proved that there were remarkable relationship between the texturing entropy change and the parameters of structure and property of the textured yarn. To find out the effects of parameters of texturing on the entropy change, a group of single factor experiments focus on representative air-jet texturing and differential shrinking parameters including filament and filaments size, the overfeeding rate in air-texturing and the differential shrinkage rate of the differential shrinkage filaments were designed. The testing results showed that, in term of a settled filament linear density, the entropy changing became bigger when the filaments linear density grew; on the contrary, if the filaments linear density was a constant, the entropy changing decline with the increasing of the filament linear density. The bigger overfeed could increase the entropy changing during the course of air texturing while the bigger differential shrinkage rate could bring a bigger entropy changing for the differential shrinkage filaments ATY.