本實驗以兩種方式製備PET電紡纖維，意即常溫橫向電紡PET/三氟乙酸 (TFA)溶液系統與高溫電紡PET/phenol溶液系統；常溫電紡探討改變不同操作參數，如電壓、流量 (Q)與溶液黏度 對cone、液柱直徑 (dj)及纖維形態(df)的影響，實際結果發現彼此間之關係式為dj~Q0.66、df~Q0.19；dj~ho0.06、df~ho0.78。高溫電紡探討油浴溫度 (T)、溶液濃度 (hw)對cone、液柱直徑及纖維直徑的影響，其關係為dj~T-0.31、df~T-0.66；dj~hw0.60、df~hw0.32。若要電紡相同直徑之纖維，使用phenol作為溶劑明顯比TFA所需要的濃度高出許多。

以轉盤收集器收集具同一方向之順向纖維膜，後以WAXD與SAXS量測PET纖維中晶體的順向性，電紡所得纖維內結晶量很少，升溫回火至110oC時發生冷結晶，並於WAXD與SAXS皆觀測到晶體之順向性，在冷結晶後纖維中的晶體依然有很好的順向性。

混掺石墨烯於PET/phenol溶液中進行電紡，可得到含有石墨烯之電紡纖維，由於石墨烯的橫向尺寸大於纖維直徑，所以纖維表面有到許多突起點判斷為石墨烯聚集，本實驗無法均勻分散石墨烯於纖維膜，使得石墨烯纖維膜的導電度低。

PET electrospun fibers have been prepared by two methods. One used the room temperature electrospinning of PET/TFA solutions in horizontal mode , and the two used high temperature electrospinning of PET/phenol solutions in vertical mode. Our research is to study the effects of the applied voltage, flow rate (Q), solution viscosity (o) and oil temperature (T) on the Taylor cone, jet diameter (dj) and fiber diameter (df). In PET/TFA system, the scaling laws between Q, ho, dj and df are dj~Q0.66, df~Q0.19；dj~ho0.06, df~ho0.78. In PET/phenol system, the scaling laws between T, hw, dj and df are dj~T-0.31、df~T-0.66；dj~hw0.60、df~hw0.32. To obtain fibers with the same diameter, the concentration of PET/phenol solutions required for electrospinning should be much higher than that in PET/TFA system.

The aligned PET fibers were collected by high speed disk rotator, and used to investigate the lamellar orientation. From WAXD and SAXS results, the as-spun fibers were nearly amorphous. After heating to 110oC, cold crystallization and the arcs which means crystal orientation were observed in WAXD and SAXS. After annealing, the crystal orientation was kept.

PET/graphene electrospun fibers could be prepared by blending graphene into PET/phenol solutions. Our research is to know where the graphene in nanofibers was located. Because the graphene size was larger than fiber diameter, graphene was included in PET fibers but protuberated. In our results, the graphene could not be dispersed well in fibers, and the electric conductivity was low.

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