本研究以同步小角/廣角X光散射鑑定電紡所得同排聚苯乙烯(iPS)順向纖維在連續升溫過程中與同排聚丙烯(iPP)順向纖維在逐步升溫過程中，纖維內微結構隨溫度的演變。
電紡所得iPS順向纖維的結構為amorphous，在溫度高於Tg時，會因為冷結晶而產生晶體。隨著溫度上升，結晶度逐漸增加，但在160 oC以上，增加幅度趨緩。此外，在120 oC下形成的晶體具有高度順向性，隨後在高溫下晶體順向性降低。SAXS分析結果表明，纖維內lamellae的順向性在不同溫度下差異性不大，並且纖維形態在100 oC時有明顯變化，這部分由SEM觀察結果證實。
電紡所得iPP順向纖維的結構主要為amorphous與mesophase，並夾帶少量a型晶體。隨著溫度上升，原本存在於纖維內的mesophase與少量型晶體逐漸變為只有a型晶體，而amorphous含量並沒有因為mesophase含量減少而增加，顯示iPP順向纖維的冷結晶過程主要是由mesophase轉換為a型晶體所主導。此外，lamellar順向性分析結果顯示，amorphous在高溫下結晶形成的lamellae順向性較高。

The evolution of the microstructure in aligned isotactic polystyrene (iPS) electrospun fibers during continuous annealing, and aligned isotactic polypropylene (iPP) electrospun fibers during stepwise annealing is characterized by synchrotron small/wide-angle X-ray scattering.
The dominant structure of aligned iPS as-spun fibers is amorphous. When the annealing temperature (Ta) achieve the glass transition temperature (Tg), relaxation of chains and cold crystallization occur. As Ta increases, the crystallinity gradually increases, but the rate of increase slows down above 160 °C. Moreover, the crystals exhibit high orientation at 120 °C, which decreases at higher Ta. SAXS results indicate that lamellar orientation of remains unchanged at different Ta.
Aligned iPP as-spun fibers consists mainly of amorphous phase and mesophase components, with a small amount of α-form crystals. As Ta increases, the mesophase and the small amount of α-form crystals initially present in the fibers gradually transform predominantly into α-form crystals, while the amount of amorphous phase does not increase despite the decrease in that of mesophase. This suggests that the cold crystallization process of aligned iPP fibers is primarily dominated by the transformation of the mesophase into α-form. Additionally, lamellar orientation analysis results show that the lamellae formed from the crystallization of the amorphous phase at high Ta exhibit higher orientation.

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