本研究利用偏光顯微鏡(POM)和掃描式電子顯微鏡(SEM)，針對聚對苯二甲酸壬二酯(PNT)所具備之兩種環帶球晶，分別為單環帶球晶形貌(稱之Type-1)及雙環帶球晶形貌(稱之Type-2)，進行光學性質的測定，及其相對應之內部晶板排列進行觀察與分析。POM觀察，隨著Tmax升高，Type-1球晶的數量分布比例及體積分布比例的效應隨之增加，然而Type-2球晶則呈現相反趨勢。進一步針對球晶成長速率進行測定，嘗試從動力學的角度解釋為何在同一個熱條件下，會有兩種環帶球晶的同時生成，但結果並不存在著差異。然而不同球晶初始成長型貌(Type-1：稻稈狀球核；Type-2：圓形球核)及後續的結晶過程(Type-1：先沿著球核兩端結晶，接著再匯集於垂直球核的方向，並等向巢位為生長；Type-2：自始至終的等向輻射性朝外圍結晶)，解釋了PNT在同一個結晶溫度(Tc)同時形成Type-1和Type-2球晶的機制。進一步應用SEM進行內部晶板結構之觀察，以期更深入的解析Type-1和Type-2的結晶機制。我們著實發現到Type-1和Type-2的內部晶板排情形，除了彼此具備一個共同的特徵：2種晶板排列之不連續性，其他排列特徵則存有甚大的差異。對於Type-1球晶，除了發現從不同角度切開樣品，會觀察到不同的晶板排列情形(沿著band：valley至ridge區域，有蜷曲(curling)的晶板生長趨勢；沿著ridge：晶板具備週期性偏折之特徵，且伴隨著如同扇狀的晶板分支)之外，當內部球核的位置較靠近上表面(殼層結構)，或是處於較深層內部(沿著球核為扇狀結構伴隨週期性偏折，而垂直於球核則是殼層結構)時，也都會進而影響內部晶板排列的形貌以及規則性。至於Type-2球晶，則觀察到許多傾斜排列的晶板，與上表面的ridge之排列形貌產生強烈的對應，而valley區域所對應的內部晶板排列，則是呈現出與ridge區域相當大的差異。當我們進一步增厚Type-2球晶厚度，結果發現到當給予足夠之生長空間時，高分子晶板也會呈現出扭轉(twisting)的結構。因此，在藉由POM和SEM的鑑定分析後，本研究詳實的呈現出Type-1和Type-2不同的球晶成長形貌與機制。

Dual types of ring-banded morphology of PNT, which are single ring-banded morphology (Type-1) and double ring-banded morphology (Type-2), are investigated by polarized optical microscopy (POM) and scanning electron microscopy (SEM) to understand the exact crystallization mechanisms. We exploit POM to not only determine the Tmax effects on the number proportion and volume fraction of Type-1 and Type-2 spherulites over the entire sample, but also record the growth rates of both and the beginning nuclei morphology plus the subsequent spherulitic morphology captured at different time of crystallization. However, the kinetic aspects cannot explain why PNT could form the dual types of ring-banded morphology under the same thermal condition; instead, while capturing the entire crystallization process, we clearly clarify the reason. Then we take advantage of SEM to observe the interior lamellar arrangement of Type-1 and Type-2 spherulites, and to see whether any differences inside the bulk. Under such analyses, we first understand the only same characteristic existing in Type-1 and Type-2 spherulites: 2 kinds of discontinuities in lamellar arrangement. And the following examination show that the lamellae of Type-1 spherulites demonstrate the different arrangement while being observed from different dissection angle, in addition, the nuclei positions either near the top surface or more inside the spherulite also influences the arrangement and complexity of interior lamellae. As for Type-2 spherulites of PNT, we observe the strong correlation between the topography and interior lamellar assembly, that is to say, both the lamellar arrangement in top surface and inside the bulk display the tilted characteristics. More interestingly, the lamellar arrangements of Type-2 spherulites clearly demonstrate the twisting structure with enough growing space. Consequently, under the combination of POM and SEM analyses, we exactly illustrate the different crystallization mechanisms of Type-1 and Type-2 spherulites of PNT.

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