| Summary: | 碩士 === 國立臺灣科技大學 === 材料科學與工程系 === 103 === In recent years, with the development of electrospinning technology, the development of nanofiber yarn has become one of the focused research. The goal of this study is to design a continuous nanofiber yarn mechanism with high steady and high production efficient. Through Taguchi orthogonal array and analysis of variance (ANOVA), using smaller experimental frequency, shorter experimental period and lower experimental costs to evaluate the effect of each factors, the optimum parameters for different quality characteristics can be determined. Further, the multiple quality characteristics is analyzed by ANOVA and principal component analysis (PCA).
In this study, spinning 11.4tex as target, voltage is 20kV, temperature and humidity are set as 30±2℃/30±3%RH, the discussed control factors are draw ratio, nozzle size, flow rate, and elongation temperature. Draw ratio use 1.0times, 1.5times and 2.0times. Nozzle size use 20G(0.6mm), 22G(0.42mm) and 24G(0.31mm). Flow rate use 3ml/hr, 5ml/hr and 7ml/hr. Elongation temperature use 80 °C, 100 °C and 120 °C. The experiment is designed by Taguchi L9(34) orthogonal array. The considered quality characteristics are fiber diameter, fiber uniformity and fiber arrangement. Further, through the optimum design of hot drawing conditions, the strength of PAN nanofiber yarn can be improved. According to this experiment design, the feasibility of this novel mechanism for continuous nanofibrous yarn can be verified, and the result can provide the reference for technology of nanofiber yarn’s development in the future.
According to experiments, three quality characteristics of fiber diameter, fiber uniformity and fiber agreement have optimum parameters. After principal component analysis, characteristics occurs as nozzle is 22G, flow rate is 7ml/hr, draw ratio is 2 and hot elongation temperature is 120 °C. In addition, the tensile of nanofibrous yarn is 2.72cN/tex
This study use 7.4 degree of twist and 25 coefficient of twist get yarn fitness 11.4tex, set it as target, experiment of yarn fitness is about 7.4tex to 12tex. After physical characteristics test, the yarn fitness of 10.95tex is more uniform and has more stress. According to these experiments, the higher the draw ratio and elongation temperature, the higher the strain.
|
|---|
