本研究以高溫電紡不同濃度對排聚丙烯(sPP)的o-DCB溶液，製備直徑約130-350 nm之sPP纖維。為避免凝膠於電紡製程中形成，先以示差掃描卡計(DSC)測定不同濃度溶液凝膠形成的溫度，再控制電紡油浴溫度為80 oC，使電紡液溫度高於凝膠形成溫度。實驗探討不同含量的鹽類、不同濃度的溶液與以靜態鋁板或快速轉動碟盤收集方式，研究這些變數對電紡纖維的影響。
經由廣角X光繞射(WAXD)、小角X光散射 (SAXS)以及DSC分析電紡纖維微結構。以靜態鋁板收集所得纖維微結構隨溶液濃度不同而有所差異，當濃度低時電紡所得纖維主要為mesophase晶型；當濃度提高時有較多的Form I產生，是因為較高的溶液黏度導致成形纖維中可結晶的分子鏈並未完全結晶，在收集後於室溫下持續結晶成Form I晶體，此現象可由FTIR證實。而快速轉動碟盤收集所得纖維內有較多mesophase存在，這是由於額外的拉伸力所造成。藉由同步輻射光源所得變溫2-D WAXD/SAXS圖譜，可深入探討回火效應對纖維內晶體轉換的影響。在升溫過程中mesophase隨即熔化直到90 oC時完全消失，熔化過程中在較低溫度(35-60 oC)時有Form II晶體的生成，而在較高溫度(60-110 oC)時則生成了Form I晶體。

Syndiotactic polypropylene (sPP) fibers with a diameter of ca. 130-350 nm were successfully produced from high-temperature electrospinning of sPP/o-DCB solutions. To avoid gel formation during process, a jacket-type heat exchanger was used to maintain the solution temperature higher than the gel formation temperature, determined from differential scanning calorimeter (DSC). Several processing factors were investigated to elucidate their effects on the fiber diameter, which included the salt content, the sPP concentration, and the fiber collecting method by using either a stationary plate or a rotating disc.
Through wide-angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS), and DSC analyses, the internal structure of as-spun fibers was characterized. For the sPP fibers collected by a stationary plate, mesophase is the dominant structure and the content of Form I is increased with increasing sPP concentration. The formation of Form I crystal is due to the post-crystallization of the un-crystallizing species at room temperature, which was confirmed by long time FTIR traces. For the sPP fibers collected by a rotating disc, the amount of mesophase was increased since a high stretching force was induced. By the variable-temperature 2-D WAXD/SAXS with synchrotron radiation, the crystal variation of sPP fibers was investigated. On heating, the mesophase starts to melt and disappears completely at 90 oC. Simultaneously, Form II crystal is developed at low temperatures (35-60 oC), followed by the formation of Form I crystal at high temperatures (60-110 oC).

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