本研究配製不同濃度尼龍 6/甲酸溶液，以電紡絲法製備尼龍 6纖維，並探討纖維形態的變化；另外以WAXD、SAXS和FTIR探討升溫時纖維內晶型的變化。由SEM觀察得知濃度高的溶液所製備的纖維較粗，22 wt%溶液所得纖維形態為彩帶狀。DSC升溫過程中發現彩帶狀纖維在約235 oC存在一特殊的高溫相，其量佔纖維結晶度的28 %左右。改變電紡環境，發現濕度並非高溫相形成的主要原因。為了觀察此高溫相的晶型，以同時WAXD/SAXS探討逐步升溫纖維熔化過程，發現在230 oC已無明顯晶體結構。然而以FTIR偵測在235 oC下仍存在一與alpha晶型相關之 1201 cm-1吸收峰。

在芯鞘型纖維製備方面以尼龍 6/甲酸為外管流體，聚氧化乙烯/氯仿為內管流體，探討流量和內管溶液濃度對同軸電紡製程的影響。觀察cone內部的變化，發現在較高流量下和內管溶液濃度較高時，cone內部可以穩定；由SEM觀察以水萃取聚氧化乙烯後的芯鞘型纖維形態和其截面，可看到破裂或坍塌狀的Nylon 6纖維和孔洞直徑大小不一的Nylon 6中空纖維。

Our research is to prepare Nylon 6 fibers by electrospinning of solutions with different concentrations in formic acid. WAXD, SAXS, and FTIR were used to study the crystal modification and effect of annealing temperature on crystal transformation in Nylon 6 fibers. As demonstrated by SEM, ribbon-like fibers were obtained when the 22 wt% solution was electrospun. DSC heating traces on the ribbon-like fibers exhibited an unusually high melting temperature of ~235 oC, indicating the presence of a high-temperature phase (HT phase). Depending on the processing conditions, the contents of HT phase could be as high as 28 % of the fiber crystallinity. To change surrounding conditions of electrospinning, humidity is not the factor of formation of the HT phase. To reveal the HT phase, simultaneous WAXD and SAXS using synchrotron radiation on the fiber mats during stepwise annealing were performed, but featureless structures were obtained at temperatures higher than 230 oC. In contrast, in-situ FTIR spectra clearly demonstrated the residual presence of an alpha form-related band of 1201 cm-1 at 235 oC.

To prepare core/shell fibers, we used Nylon 6/formic acid as shell fluid and PEO/chloroform as core fluid, and discussed the effects of flow rate and concentration of core solution on the coaxial electrospinning. We observed the variation of cone. The cone could be stable when flow rate was higher and concentration of core solution was higher. After the PEO core component had been extracted by H2O, the morphology of hollow Nylon 6 fiber were collapsed or cracked. Different diameters of holes of hollow Nylon 6 fiber were also obtained after extracted.

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