本研究使用鄰二氯苯為溶劑配置超高分子量聚苯乙烯，針對濃度0.5 wt.%溶液電紡，探討液柱形態以及甩動速度之關係，及與相同濃度的二甲基甲醯胺作為溶劑之溶液比較。

以氦-氖雷射光打擊電紡0.5 wt.%溶液液柱，沿赤道方向掃描距針底(z=0)不同距離所得之散射圖案，根據掃描強度分布所得第一個強度最大值所對應散射向量值(qm1)經過dj=/qm1得知液柱直徑(dj)，值經過Mie theory計算可得12.33，找到關係式dj(z)~z-n，n值為-0.64。

使用乾玻片收集液柱中段，以OM觀察液柱因表面張力分段數個結構，且各結構因水氣誘導相分離外觀含有微結構。以含有非溶劑甲醇之silicone rubber spacer收集液柱中段，SEM發現液柱中由數條線狀結構組成，線狀結構間有相分離，以OM觀察線狀結構，其中含有更微小線狀結構及珠狀結構。

以高速攝影機觀察電紡溶液液柱甩動行為，測量液柱甩動而形成之波形隨時間變化，可得知波形軸向速度與側向速度，在溶劑揮發忽略假設下，利用質量守恆式(dj2(z)=4Q/Vj(z))計算液柱直徑，且與雷射結果比較。

以SEM及TEM觀察電紡0.5 wt.%溶液產物，得知此濃度之糾纏程度還未能得到均勻的纖維，部分電紡產物仍為液體，此液體會發生viscoelastic phase separation。

In this study, o-dichlorobenzene was used as a solvent to prepare ultra-high molecular weight polystyrene solution, and the solution was electrospun for a concentration of 0.5 wt.%. The relationship between the jet morphology and the whipping velocity was investigated, and compare the same concentration of dimethylformamide with the solvent solution.

He-Ne laser showed on the electrospinning jet of 0.5 wt.% solution, and the scattering pattern, which is at different distances from the bottom of the needle (z=0) on the screen behind the jet were scanned along the equator direction to obtain the intensity profile. From the profile, the magnitude of the scattering vector of the first intensity maximum (qm1) was determined. The jet diameter profiles (dj(z)) obtained by dj(z)=/qm1. The  value is calculated by Mie theory to obtain 12.33, and the decaying rate of dj(z) with z follow a scaling law of dj(z)~z-n.the value of expotent n is -0.64.

Slide was used to collect the middle section of the liquid jet. In OM observation, liquid jet was divided into several structures because of the surface tension, and each structure appearance contained a microstructure due to the non-solvent-induced phase separation. In order to freeze the structure inside the jet, the silicone rubber spacer containing non-solvent (methanol) were used collect the middle section of the liquid jet. In SEM observation, the liquid jet consisted of several string structures, and each string structures had phase separation. The string structure, which contained a more small string structure and beaded structure was observed by OM.

By observing the whipping behavior of the electrospinning jet with a high-speed camera and measuring the waveform of the liquid jet and changing with time can know the axial velocity and lateral velocity of the waveform. Under the assumption of solvent evaporation neglect by using the mass balance (dj2(z)=4Q/Vj(z)) to calculate the liquid jet diameter and compare it with the laser results.

The electrospinning 0.5 wt.% solution product was observed by SEM and TEM. It was found that the degree of entanglement of this concentration could not obtain uniform fiber, and some products were still liquid, and this liquid would undergo viscoelastic phase separation.

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