本研究使用鄰二氯苯做為溶劑配製亂排聚苯乙烯溶液並在室溫下電紡14、21與28 wt. %溶液，其在25 oC下黏度分別為514、3828與23328 cP(etao)，探討溶液黏度對電紡液柱與纖維直徑(df)的影響。

以氦-氖雷射光打擊電紡不同濃度溶液所得液柱，分別沿赤道方向掃描距針底(z=0)不同距離處所得散射圖案，由掃描所得強度分布圖中第一個強度最大值對應的散射向量值(qm1)計算液柱直徑(dj(z)):dj=beta/qm1，14、21與28 wt. %溶液對應的beta由Mie theory可得分別為12.61、12.69與12.76。發現不同溶液濃度下均存在dj(z)~z-n關係式，n值分別為1.32、1.55與0.58。發現液柱尾端直徑(dj,e)隨溶液黏度上升而有小幅度地增加，dj,e~etao0.14。在溶劑揮發可忽略的假設下，可利用質量守恆式計算液柱速度(Vj(z)=4Q/pidj2(z))，發現液柱尾端處的速度(Vj,e)隨黏度上升而下降。

使用乾玻片收集中、尾端的電紡液柱，以SEM可觀察到其表面具有直徑為0.14~0.38 um的孔洞結構。以含有非溶劑甲醇的玻片收集中、尾段的液柱，使aPS析出以保留結構。在SEM下發現液柱具有裂痕，可進一步觀察到液柱內部存在排列整齊的條狀結構。
以高速攝影機觀察電紡不同濃度溶液所得液柱甩動行為。將whipping區間中液柱的甩動形態分為兩種，水平甩動與螺旋甩動。分別測量不同形態下液柱因甩動而形成的波形隨時間的變化，可得液柱的側向與軸向速度，發現均隨溶液黏度增加而下降。

最後以FT-IR分析電紡不同濃度溶液所得纖維是否具有與分子鏈形態相關的1262、1098與803 cm-1的吸收峰存在，結果顯示均只存在接近1098 cm-1的1091 cm-1吸收峰。

In this study, o-DCB was used as solvent to prepare aPS/o-DCB solutions. In order to reveal the effects of solution viscosity on the diameters of the electrospinning jet and as-spun fibers, the electrospinning of aPS/o-DCB solutions with 14, 21 and 28 wt.% were performed at room temperature. The measured viscosities of the three solutions at 25 oC are 514, 3828 and 23328 cP, respectively.

He-Ne laser beam was showed on the electrospinning jet with different concentrations, and the scattering patterns on the screen behind the jet were scanned along the equator direction to obtain the intensity profiles. From the profile, the magnitude of the scattering vector of the first intensity maximum (qm1) was determined. Jet diameter profiles (dj(z)) obtained from the solutions with different concentrations were constructed by using dj(z)=beta/qm1. The calculated beta values which obtained from Mie theory are 12.61, 12.69 and 12.76 for 14, 21 and 28 wt.% solution. The decaying rate of dj(z) with z follows a scaling law of dj(z)~z-n. The values of exponent n are 1.32, 1.55 and 0.58 for 14, 21 and 28 wt.%, respectively. The jet diameter at straight jet-end position (dj,e) slightly increased with increasing solution viscosity, it follows a scaling law of dj,e~etao0.14. Assuming that no solvent evaporation took place in the straight jet region, the jet velocity (Vj) could be calculated by mass balance: Vj(z)=4Q/pidj2(z). The jet velocity at jet-end position (Vj,e) decreased with increasing solution viscosity.
Slides were used to collect liquid jet during electrospinning. In SEM observation, there are porous structures with diameter of 0.14 to 0.38 um on the surface of collected jet. In order to freeze the structure inside the jet, slides with dropped non-solvent (methanol) were used to collect liquid jet. Some jet with cracks on the surface can be observed in SEM images, there are oriented string structures inside the jet.

Using high-speed camera to observe the behavior of electrospinning jet obtained from aPS solutions with different concentrations. In jet whipping region, the jet behavior can be classified into two different types, one is the horizontal whipping mode and the other is the spiral whipping mode. We measured the positions of wave-like jet with time to obtain the lateral and axial velocities of jet. They both decreased with increasing viscosity.

Finally, FT-IR was used to characterize the as-spun aPS membrane to check whether it have three absorption bands of 1262, 1098 and 803 cm-1. These three bands relate to the structures of molecular chain in as-spun fibers. From the results, it shows that only one band of 1098 cm-1 which closes to the band position of 1091 cm-1 appear for the as-spun fibers obtained from 14, 21 and 28 wt% solutions.

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