本研究使用去離子水為溶劑製備聚乙烯醇水溶液，於室溫下電紡濃度7 wt.%水解率88、98-98.8 %溶液，探討不同水解率對電紡聚乙烯醇的影響。

以氦-氖雷射光打擊電紡兩種水解率溶液液柱，沿著赤道方向掃描距針底(z=0 mm)不同距離之散射圖譜，將所得強度分佈中亮峰的位置，以Mie theory模擬出的強度分布做擬合，得到電紡DH=88與98-98.8 %時dj(z)~z-n的關係式，其中n值分別為-1.70與-1.82。

使用乾玻片收集電紡時液柱中段部分，以OM觀察液柱內部無方向性且為溶劑未揮發的狀態下被收集到，因為表面張力使得液柱邊緣非平滑狀。以含有非溶劑正丙醇之silicon rubber spacer玻片收集液柱中段部分嘗試保留住液柱內的結構，並觀察隨時間的變化，發現當非溶劑揮發後在液柱表面出現一層液膜，這層液膜會隨時間而消失，且收集到的液柱為多根較細的液柱所組成。

以高速攝影機觀察電紡液柱甩動行為，量測液柱甩動而形成的波型隨時間變化，可得液柱的軸向與側向速度，發現水解率較高的溶液甩動速率較快。

以SEM觀察收集板上纖維發現有多根纖維聚集成一束。以TEM觀察收集針底下3 cm處纖維發現ribbon的結構且內部看到更細小可能為string的結構。

In this study, deionized water was used as a solvent to prepare polyvinyl alcohol aqueous solution, the electrospinning of PVA/H2O solutions with 7 wt.% and two kinds of degree of hydrolysis 88 % and 98-98.8 %, and compare the effects of two degree of hydrolysis on electrospinning of polyvinyl alcohol aqueous solution.

He-Ne laser showed on the electrospinning jet of two degree of hydrolysis, 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 alone the equator direction to obtain the intensity profile. Fit the position of the peak in the intensity profile with the profile simulated by Mie theory to find the jet diameter profile dj(z). The decaying rate of dj(z) with z follow a scaling law of dj(z)~z-n, the value of expotent n of degree of hydrolysis 88 % and 98-98.8 % are -1.70 and -1.82.

Slides were used to collect the middle section of liquid jet during electrospinning. In OM observation, there is no structure in the liquid jet, and it is collected when the solvent is not volatile so the boundary of the liquid jet was not uniform. In order to freeze the structure inside the jet, the silicone rubber spacer containing non-solvent n-propanol were used to collect the middle section of the liquid jet. Observe the change of collected liquid jet over time, when the non-solvent evaporates, a liquid film appears on the surface of the liquid jet, and this liquid film will disappear over time, and also find the liquid jet is composed of multiple thin liquid jet.

Using high-speed camera to observe the behavior of electrospinning jet obtain from PVA/H2O solutions with different degree of hydrolysis. Measure the axial and lateral distance of first wave which in the whipping region change with time, and find the axial and lateral velocity of jet, the velocity is faster with higher degree of hydrolysis.

The fiber on the collecting plate is observed by SEM, it is found that there are many fiber gathered into a bunch. Collected the fiber 3 cm below the needle and observed it by TEM, find ribbon-like structure and a smaller structure that may be a string is seen inside.

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