本研究利用偏光顯微鏡(polarized optical microscopy, POM)、電子顯微鏡(scanning electron microscopy, SEM)、小角度X光散射儀(microbeam small-angle X-ray scattering, SAXS)與廣角度X光繞射儀(microbeam wide-angle X-ray diffraction, WAXD)分別探討生物可分解高分子聚丁二酸丁二醇酯(poly(butylene succinate), PBSu)及聚丁二酸乙二醇酯(poly(ethylene succinate), PESu)兩系統，以熔融結晶之方式行成之球晶形貌，並觀察其結晶行為。
第一部分為PBSu系統，與作為稀釋劑的聚環氧乙烷(poly(ethylene oxide), PEO)進行摻合，用以將PBSu之晶板更為鬆散，形貌顯現的更加清楚，且PEO能簡單的被DI水所蝕刻，以利後續觀察。選定30/70之組成比例做進一步分析，以POM初步觀察球晶形貌，隨結晶溫度(crystallization temperature, Tc)上升，由環帶狀球晶轉變為特殊的複合型枝狀球晶，是以羽毛狀及蕨類狀兩種分枝共同存在的形貌。選擇Tc = 76 oC之樣品進一步以SEM觀察球晶上表面以及內部晶板結構，首次在枝狀球晶當中發現edge-on與flat-on晶板的轉換，為本實驗創新的結果，並以microbeam SAXS和WAXD之結果佐證，推測複合型枝狀球晶合理之生長機制。第二部分為PESu系統，以不定型PVPh作為稀釋劑，改變組成以及結晶溫度，初步以POM觀察球晶之形貌，在任何條件下皆是以枝狀球晶存在，並在組成70/30且在特定結晶溫度區間(Tc = 52-65 oC)會以特殊的複合型枝狀球晶(羽毛狀與蕨類狀分枝形貌共存)以及蕨類狀球晶在同一結晶溫度下存在，選定Tc = 60 oC之樣品進一步以SEM觀察球晶上表面結構，並以microbeam WAXD輔助其結果，推測複合型枝狀球晶合理之生長機制。透過本研究兩個系統之間的互相比對，皆顯示出晶板是以持續分形分枝的不連續性方式向外生長，但PBSu當中，在低溫下會形成環帶狀球晶，然而PESu當中，任何條件下皆以枝狀形貌存在，導致只有在PBSu複合型枝狀球晶當中具有晶板排列方式的轉換，PESu卻沒有此現象。

Morphologies and lamellar arrangement of biodegradable polyesters, poly(butylene succinate) (PBSu) and poly(ethylene succinate) (PESu), have been investigated.
In the first part, the morphology of PBSu changes from ring-band to composite dendritic spherulite with increasing crystallization temperature. The composite dendritic spherulites are composed of edge-on and flat-on lamellae which radiate outward from the common nucleus with fractal growth to form feather-like and fern-like dendrites respectively. The top surface and interior lamellar arrangement of the composite dendritic spherulites crystallized at 76 oC were observed by using scanning electron microscopy (SEM), and microbeam small-/wide-angle X-ray scattering (SAXS/WAXD) was used to further confirm the results observed by SEM. The reasonable growth mechanism of PBSu composite dendritic spherulite has been proposed.
In the second part, PESu only exists dendritic spherulites at any composition and crystallization temperature. At Tc = 60 oC, composite dendritic spherulites are chosen for further discussion. The top surface structure is revealed by using SEM. Furthermore, microbeam WAXD was used to assist the observation results.

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