本研究製備poly(butylene succinate) (PBS)/poly(L-lactic acid) (PLLA)同軸靜電紡絲纖維，其中芯為PBS，鞘為PLLA，討論不同參數對電紡絲纖維直徑及形貌的影響，並探討PBS和PLLA在同軸纖維中的熱性質和結晶行為。經過不同熱退火溫度處理後，PLLA的熔融峰由兩個吸熱峰組成，分別代表與α’和α的結晶型態，且熱退火溫度越高，α相的比例越高；而PBS則只出現單一的熔融峰。當熱退火溫度小於120 ˚C時，PBS和PLLA可以同時且獨立結晶，並沒有發現共結晶的現象，熔融焓與晶粒尺寸皆隨熱退火溫度上升而增加，但PBS熔點下降；當熱退火溫度為140 ˚C時，PBS轉變為非晶相而沒有結晶行為發生。此外，隨著熱退火溫度上升，PLLA的晶格間距變小，而PBS的晶格間距則維持不變。在PBS熔融結晶的研究中，結晶溫度會影響PBS及PLLA的結晶行為。當結晶溫度為80 ˚C時，PBS和PLLA因高溫下分子鏈的流動性較佳，在系統中兩高分子鏈段較容易各自聚集後結晶，生成的晶粒尺寸和結晶度皆較結晶溫度低時大，晶格間距則較結晶溫度低時小。在水解測試中，同軸纖維的重量損失百分比皆高於單一PBS和PLLA纖維，此特性有助於醫用材料領域的應用。

In this study, we investigated the effects of various parameters on the diameter and morphology of the electrospun coaxial fibers, with poly(butylene succinate) (PBS as the core and poly(L-lactic acid) (PLLA) as the sheath, along with the thermal properties and crystallization behavior of PBS and PLLA within the coaxial fibers. After thermal treatment at different annealing temperatures, the melting peak of PLLA was composed of two endothermic peaks, corresponding to the α' and α crystalline forms, with a higher proportion of the α phase at higher annealing temperatures. In contrast, PBS exhibited a single melting peak. When the annealing temperature was below 120 °C, PBS and PLLA crystallized simultaneously and independently, without co-crystallization. The melting enthalpy and crystallite size of both polymers increased with higher annealing temperatures, while the melting point of PBS decreased. At an annealing temperature of 140 °C, PBS turned into an amorphous phase with no crystallization behavior observed. Additionally, as the annealing temperature increased, the lattice spacing of PLLA decreased, while that of PBS remained unchanged. In the study of PBS melt crystallization, the crystallization temperature affected the crystallization behavior of both PBS and PLLA. At a melt crystallization temperature of 80 °C, due to the better chain mobility at high temperatures, both polymer chains were more likely to aggregate and crystallize, resulting in larger crystallite size and degree of crystallinity compared to lower melt crystallization temperatures, with smaller lattice spacing. In hydrolytic degradation tests, the weight loss percentage of the coaxial fibers was higher than that of single PBS and PLLA fibers, a characteristic beneficial for applications in the medical materials field.

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