許多結晶性高分子於常溫時無法溶解於一般溶劑，藉由高溫電紡裝置，可使溶液保持完全溶解的均勻態，進而製備出纖維膜。但於高溫的系統中，高分子溶液會因為溫降太大，使懸在針頭前端的液滴凝膠化，造成電紡不穩定，本研究利用遠紅外線加熱器，可提高電紡環境溫度，改善針端之阻塞，以達操作的目標。

利用高溫電紡sPS/oDCB溶液製備sPS纖維膜，其纖維直徑小於200nm，但液滴凝膠化仍使得電紡不穩定。為避免凝膠形成，使用高分子共混的方式，加入分子量為300k g/mol之aPS-H，改變sPS/aPS-H相對比例，降低sPS含量達到實驗需求，結果顯示還是無法穩定電紡製程。

本研究另對PHB溶液系統進行電紡實驗，選取室溫電紡絲可製備均勻纖維的PHB溶液濃度，提高溶液溫度可使黏度下降，因此可製備更細的纖維。於室溫下，6wt% PHB溶液利用電紡所得纖維直徑為2.04um，若將溶液溫度提高至41oC，纖維直徑降低至1.67um。另由12wt% PHB溶液於高溫電紡實驗中發現，纖維直徑可由室溫電紡之13.82um降至7.09um(41oC電紡)，下降幅度為48.7%。研究中發現，提高溶液溫度，jet length會縮短，所得纖維直徑會變細。

The objective of this study is to develop a high-temperature electrospinning apparatus applicable to the semi-crystalline polymers, which are not readily dissolved in common solvents at room temperature. At present, we successfully set up a jacket-type heating device with an IR emitter to maintain the electrospinning solutions at high temperatures for prohibiting the polymer precipitation during process due to the possible temperature drop.

By high-temperature electrospinning of the sPS/oDCB solution, sPS nano-fibers were prepared. However, the process was unstable due to the gel formation. In order to lower the temperature of gel formation, we electrospun the sPS/aPS-H blend solution with various ratios to improve the electrospinnability. But a stable processing condition was hand to reach.

In addition, we also testified the high-temperature electrospinning apparatus by using the PHB solutions. For the 6wt% PHB solution, the fiber diameter was 2.04um by room-temperature elecrospinning process. When the solution temperature was increased to 41oC, the electrospun fiber diameter was decreased to 1.67um. For the 12wt% solution, the as-spun fiber diameter was via range from 13.82 to 7.09um, depending upon electrospinning temperature. This study confirmed that fiber diameter and jet length could be reduced by increasing solution temperature.

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