本研究分成兩個部分，首先以自行設計架設有hot stage的FT-IR，來測試經逐步升溫後的aPS、sPS和iPS三種聚苯乙烯的順向纖維膜，其分子鏈orientation的變化，進而探討在結晶前，分子鏈是否發生了relaxation現象。實驗發現經逐步升溫回火FT-IR實驗後，iPS和aPS順向纖維dichroic ratio(D)在結晶前會明顯下降，代表iPS纖維在結晶前具有明顯的relaxation現象發生，而sPS順向纖維膜D在結晶前沒有明顯改變，代表sPS纖維膜在結晶前沒有明顯的relaxation現象發生。
將aPS與厚度約為3.5 nm石墨烯(graphene)的混摻溶液經電紡製備成含有不同graphene含量的aPS/graphene奈米複合纖維，直徑約100-400 nm。由Raman圖譜可知，本實驗所使用的graphene粉末G band強度明顯高於D band，代表此graphene的sp2結構較sp3結構多。由SEM和TEM影像可知，aPS纖維表面有些不規則突起的地方，推測可能是因為aPS纖維太細所以無法有效的包覆graphene。隨著aPS溶液graphene含量上升，在溶液性質方面，溶液導電度和溶液黏度也會上升，由CCD影像可知，cone height會上升而液柱長度會下降，將SEM影像配合imageJ軟體計算，可得纖維直徑會變得更細。導電度測試結果顯示aPS/graphene複合纖維膜之導電percolation threshold為0.39 vol%，可知aPS/graphene複合纖維膜石墨烯含量在0.39 vol%以上，就能形成導電網路。
本實驗希望利用已達entanglement的aPS溶液包覆未達entanglement的sPS溶液進行電紡，最後利用溶劑萃取將aPS帶走的方式得到sPS均勻纖維，但受限於目前所使用的實驗手法依舊無法克服連續製程中斷的問題，所以本實驗還未能獲得含graphene之sPS電紡複合纖維膜。

In the first part, we will discuss the relaxation behavior of aPS、sPS and iPS aligned fibers before crystallization by polarized FT-IR with hot-stage. The chain orientation in the as-spun fibers was characterized by the dichroic ratio (D) obtained from the polarized FT-IR spectra. After the stepwise heating process, the calculated D for aPS and iPS before crystallization decreased obviously, that is, iPS took place relaxation obviously before crystallization and sPS almost unchanged, that is, sPS almost did not take place relaxation before crystallization. In the second part, in order to prepare aPS/graphene conductive fiber membranes network, we elecrtospun aPS/graphene blend solution to obtain. During the experiments, we used Raman spectra、viscometer、conductivity meter, etc. instruments to analyze conductive fiber membranes properties. For the results and conclusions, first, graphene powders have more sp2 structure. Second, graphene size was larger than fiber diameter, graphene was included in aPS fibers but protuberated. Third, as graphene concentration rises, conductivity (k)、viscosity (ho) of solution and cone height (Hc) rises but jet length (Lj) and fiber diameter (df) decreases. Forth, the percolation threshold of aPS/graphene fibers is 0.39 vol%, that is, graphene contents increase to 0.39 vol% forming a conductivity network. In the third part, because we did not overcome continuous process of electrospun sPS, we did not obtain the sPS/graphene composite fibers at present.

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