本研究以PS、PAN溶液進行電紡絲製備core/shell複合纖維，探討不同操作變數，如針徑、內管黏度、內外管流量、操作電壓等，對電紡操作穩定性、cone與jet長度變化、液柱直徑與纖維直徑的影響。並利用雷射繞射法求得內外層液柱直徑；加入螢光劑FITC於PS溶液中，以螢光顯微鏡觀察纖維，並將纖維以環氧樹脂包埋後超薄切片以TEM觀察，並使用適當溶劑洗去core或shell部分之高分子確認core/shell結構存在。

實驗發現使用ND-1紡口，PS/PAN core/shell系統，core流體黏度(hc)、core、shell流體流量(Qc、Qs)、操作電壓(V)的改變對纖維外徑(Df)及液柱內外徑(dj、Dj)存在著scaling law的關係式分別為：Dj ~ hc0.07、Df ~ hc0.10；Dj ~ Qs0.15、dj ~ Qs0.17、Df ~ Qs0.07；Dj ~ Qc0.30、dj ~ Qc0.32、Df ~ Qc0.61；Dj ~ V-1.06、dj ~ V-0.93、Df ~ V-0.72。

若使用ND-2紡口，PAN/PS core/shell系統，scaling law的關係式為：Dj ~ Qs0.47、dj ~ Qs0.42、Df ~ Qs0.41。

實驗發現，不論操作變數如何改變，可得一纖維外徑與液柱直徑相關的精通曲線，即：Df = mDjn，m與溶液性質有關，對PS/PAN系統而言：m=0.129，n=1.37；但對PAN/PS系統而言：m=0.851，n=0.85。

By the electrospinning process, we prepared core/shell fibers of PS/PAN. We discussed the effects of processing variables such as needle size, core fluid viscosity, core flow rate, shell flow rate and applied voltage on the core/shell electrospinnability. Based on the laser diffraction method, the diameters of core and shell jets were measured. Fluorescence microscope (FM) and transmission electron microscope (TEM) were used to reveal the core/shell structure. For a given solution, supposition of all data available for Df and Dj is obtained regardless of the processing variables, suggesting the intimate relation between Df and Dj. A simple relation is given as follows:Df = mDjn, where m is a pre-factor depending upon the solution properties and the exponent n is approximately constant. For the PS/PAN core/shell system, values of m and n were found to be 0.129 and 1.37, respectively. For the PAN /PS core/shell system, m=0.851 and n=0.85.

Scaling laws were obtained to reveal the effect of the core fluid viscosity (hc), core/shell jet diameters (dj, Dj), fiber shell diameter (Df), and applied voltage (V). The corresponding results are shown as follows:
For ND-1 needle and PS/PAN core/shell fluids:Dj ~ hc0.07, Df ~ hc0.10; Dj ~ Qs0.15, dj ~ Qs0.17, Df ~ Qs0.07; Dj ~ Qc0.30, dj ~ Qc0.32, Df ~ Qc0.61; Dj ~ V-1.06, dj ~ V-0.93, Df ~ V-0.72.
For ND-2 needle and PAN/PS core/shell fluids:Dj ~ Qs0.47, dj ~ Qs0.42, Df ~ Qs0.41.

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