本研究主要利用掃描式電子顯微鏡(scanning electron microscopy, SEM)及斷裂厚膜試片的方式，針對聚己二酸二乙酯[poly(ethylene adipate), PEA]及聚己二酸二丁酯[poly(1,4-butylene adipate), PBA]兩脂肪族聚酯類高分子所形成的雙環帶狀球晶進行內部結構分析。
PEA於28 oC下形成的環帶狀球晶內部呈現多層堆疊的洋蔥狀結構，層中主要由徑向的片板狀晶板和纖毛狀晶板構成，層間以極薄的切線方向排列的纖毛狀晶板連接，其中存在部分90度彎折並向外轉向徑向方向。切線方向的纖毛狀晶板延伸至上表面會向球晶外圍的方向分枝及彎曲，和傾斜的徑向晶板匯集並向上穿透出上表面，於上表面形成峰部。較為突出且寬度較寬的峰部對應至下方是較為傾斜的徑向晶板；反之，越窄的峰部對應至下方是越平緩的徑向晶板。PBA於30 oC下形成的環帶狀球晶，內部同樣為多層堆疊的洋蔥狀結構，主要由徑向晶板和相對PEA較寬的切線方向晶板帶堆疊，其中切線晶板帶中存在彎曲、扭曲甚至是扭轉的晶板。另外，徑向晶板帶的中央有90o彎折的情形，形成一股極薄的切線晶板帶，使得PBA層狀結構以徑向-切線-徑向-切線的方式排列。PBA於33度下結晶，所形成的連續性纖維放射狀球晶中，並沒有發現以切線方向排列的晶板帶，故以切線方向排列的晶板的存在決定了PBA是否形成多層結構，並且證明了PBA環帶狀球晶中存在以切線方向排列的晶板。
過去普遍認為和PEA化學結構相似的PBA，其所形成的環帶狀球晶是由扭轉晶板所構成的。透過以三維角度的觀察研究後發現，PBA和PEA環帶狀球晶的三維內部構造同為多層堆疊的洋蔥狀結構，且層中構造雖存在結構上的差異，但同樣具有徑向和切線方向交替排列的情形，層與層之間主要仍呈現不連續的情形，彼此間並不具有連續轉變的過渡帶。而環帶狀球晶中雖然存在部分晶板彎曲、分枝甚至是扭轉等情形證實了晶板會扭曲，但都沒有證據顯示以球晶中心向外、連續性螺旋狀的扭轉晶板存在於球晶中，證明了脂肪族聚酯類所形成的環帶狀球晶並非以螺旋扭轉的晶板構成。

By 3-D SEM observation on the dissected bulk sample of poly(ethylene adipate)(PEA) and poly(butylene adipate)(PBA), which have ability to form double ring-banded morphology, more complete images on polymer self-assembly are obtained. PEA top surface exhibits different width of the ridge caused by the different angle between top bowl-like profile and radially orientation lamellar packing. Interior of the bulk banded PEA sample show discontinuous layer structure seems like onion. Each layer is constituted by radial direction plate-like lamellar attaching cilia-like lamellar and tangential cilia-like lamellar. Tangential cilia-like lamellar will bend in radial direction and combine with plate-like lamellar. The detailed lamellar structures gained from the observation to the bulk sample bring forth the correlation between the interior and top-surface lamellar structures. With better techniques and preparation samples, the wider variation of point of view provided by the 3-D observation offers clearer images than what provided by the 2-D observation. SEM micrographs of PBA banded spherulite also exhibits layered-structure. Each layer composed of tangentially- and radially oriented lamellae though the regularity is lower than PEA banded spherulite. Banding and twisting lamellae are found in the radially oriented layer. This phenomenon caused PBA banded structure more irregular. Both PEA and PBA banded spherulites show multi-layered structure and shape into onion like. The interior micrographs show discontinuous multi-layered structure and prove that banded spherulite is not composed of continuously twisting lamellae from the nucleus to the outer periphery.

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