本研究的主要目的為，以光散射的方式，分析室溫下電紡絲聚乙烯醇水溶液(DH= 98-98.8%、88%)的液柱，以及液柱內微結構的大小，以釐清高分子水溶液在電紡絲過程中的變化。

本實驗室呂品賢學長於2020年發表之碩士論文內，收集電紡絲聚乙烯醇水溶液時的液柱，以TEM觀察。除了液柱外，內部可見高分子更為密集的部份。據此本實驗室提出一新的電紡絲纖維成形機制：溶液中高分子纖維的成形並不是在whipping的階段才直接產生；而是在液柱內，polymer rich的部份逐漸聚集，最後當溶劑揮發之後，才形成纖維。綜上所述，本研究希望可以觀察在電紡絲的過程中，高分子溶液在電紡絲時液柱內的變化，以進一步確認高分子纖維形成的過程。

實驗使用氦-氖雷射打擊電紡絲的液柱，觀察幕上的光散射強度分布，以Mie theory計算出的強度分布擬合電紡絲液柱的散射強度分布。另外，希望能以本實驗室推導之方程式分析液柱內微結構的散射強度分布。

實際上，以Mie theory無法合理擬合實驗所得的光散射強度分布。因此需克服因視角造成相機拍攝幕上的光散射強度低於預期；以及將收集高(theta > 45°)、低散射角(theta < 45°)光散射強度分布的兩個幕，所得到的數據合併的問題。

We use DH= 98-98.8 and 88% PVA to prepare 7wt% aqueous solution for electrospinning. By CCD image and laser light scattering, we can measure the dj and further calculate vj and extension rate. We find that the extension reaches ~500 s-1, the relaxation rate of the solution, around the apex. This is a proof that the progression of phase separation starts before whipping happens.

When looking into the feature of the equation of Mie theory, we find that: (1) Instead of a straight line, the relationship of I(q=0) and RA looks like a wave. (2) When RA is large enough, RA ~ qm1-1.

For equation of string-like microstructure, the position of qm1, qm2 and qm3 is like that of R. G. B. theory.

For pattern of light scattering on the screen, the angle from the center line of the camera will affect captured intensities. By using beam splitter, we can measure unaffected and affected intensities at the same time. The relationship of biased intensity and the angle can be shown as I/I0 ~ tan phi-4.84.

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