本研究利用原子力顯微鏡(atomic-force microscopy，AFM)、環境式掃描電子顯微鏡(environmental scanning electron microscopy，ESEM)，偏光顯微鏡 (polarized optical microscopy，POM)來探討兩成份摻合系統聚氧化乙烯 [poly(ethylene oxide)，PEO]/高分子量─左式聚乳酸 [poly(L-lactic acid)， PLLA] 與聚氧化乙烯 [poly(ethylene oxide)，PEO]/右式聚乳酸 [poly(D-lactic acid)，PDLA]之球晶形貌、晶板微結構、成長機制等分析，並觀察上蓋效應、膜厚與旋光性對晶體所造成的影響。
本研究利用熔融結晶的方式觀察此PEO/ PLLA與PEO/PDLA混摻系統，首先利用玻片作為上蓋觀察球晶形貌的影響，結果顯示有加上蓋之樣品於Tc=120°C其形貌在不同組成下皆呈現環帶狀球晶，其原因為PEO及PLLA(PDLA)表面自由能不同所致。接著，觀察當膜厚較厚時，生成較規則的螺旋狀環帶球晶，且PEO/ PLLA與PEO/PDLA旋轉方向分別為逆時針與順時針；當膜厚較薄時，則生成樹枝狀結晶，依彎曲方向來區別則是S形與Z形，判斷此現象是因為chirality的差異所致；接著，為了更清楚看到PLLA(或PDLA)晶板排列方式，將樣品水洗蝕刻後，則透過SEM針對摻合比例為80/20在120°C下結晶的樹枝狀結晶與環帶球晶作斷裂面的觀察。由樹枝狀結晶可發現其主幹與枝幹的lamella皆已edge-on的方式排列；而環帶狀球晶之晶板則是以週期性波浪狀的方式連續排列但卻非常不規則，且依球晶形貌彎曲方向，推論聚乳酸chirality之關係、PEO的存在、膜厚等皆為造成此形貌的重要因素。

Effects of cover, film thickness and chirality in poly(ethylene oxide)/poly(L-lactic acid) (PEO/PLLA) and poly(ethylene oxide)/poly(D-lactic acid) (PEO/PDLA) blend systems were observed by polarized optical microscopy (POM), scanning electron microscopy (SEM), atomic-force microscopy (AFM). This study was focused on the ring-banded and dendritic spherulites crystallized at 120 °C with different thickness in PEO/PLLA (80/20) and PEO/PDLA (80/20) blends. From melt-crystallization, the ring-banded pattern always showed in the samples with cover in different compositions at Tc=120°C. The phenomenon was caused by the different surface energy of PEO and PLLA (PDLA). Another part is the observation of spherulitic morphology by controlling the film thickness. Ring-banded morphology appeared in thicker films, while the dendrite crystals were obtained in thinner films. Banded spherulite of PLLA and PDLA formed at Tc=120°C shows counter-clockwise and clockwise rotations, respectively, attributed to the opposite molecular chirality. The lamellae of dendritic spherulites formed at Tc=120°C exhibit the sense of curvature which is S-shaped for PLLA, but Z-shaped for PDLA. The lamellar arrangement and orientation were further investigated by fracturing across the PEO/ PLLA (80/20) and PEO/PDLA (80/20) blends samples then removing the PEO content. Lamellae in PLLA and PDLA banded spherulites in thicker films show loose but continuous lamellar arrangement, periodically waving from edge-on to flat-on lamellae across ridge to valley regions in radial direction. For dendritic morphology in thinner films, the main branch and side branch of the spherulite were aggregated with edge-on lamellae. The result indicating that the molecular chirality, the existence of PEO, film thickness and so forth were the important factors leading to these spherulitic morphology.

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