共軛高分子的溶液結構可以由於記憶效應而對成膜自組裝行為和結構造成很大影響。在這項研究中，我們研究溶液老化對P3HT和PBTTT-C14鎔鑄成膜後結晶動力學產生的效應。 P3HT可溶解在氯苯（CB）和四氫呋喃（THF），其中，CB是一個比THF更好溶劑，以形成宏觀上均勻的溶液。我們將所得溶液在室溫下以不同時間老化觀察長達兩週。結果發現，由CB鎔鑄的 P3HT薄膜之結晶動力學在經過老化後表現得不受影響。另一方面，老化作用在由THF鎔鑄的 P3HT薄膜產生明顯的影響，其中來自老化較長時間的溶液薄膜表現出較低的初始結晶度和較慢的結晶速率。而結晶動力學的遲緩是歸因於奈米鬚晶結構在老化溶液中的發展。在CB溶液的情況下，這樣的形態實體由P3HT結晶老化過程的發展是較小的，使得發生在該膜上均勻的無定形基質結晶。在THF溶液的情況下，由於較差的溶劑質量老化過程中形成的奈米晶鬚被轉移到薄膜。該奈米鬚晶實體在熔融狀態下仍可保持穩定，因此在冷卻時所施加的拓撲約束到隨後的結晶。在這種情況下，P3HT的結晶發生在由奈米鬚的聯網約束的網絡，進而延緩結晶動力學。
在PBTTT-C14的例子，我們是使用鄰二氯苯溶液鎔鑄成膜。我們已經發現，溶液老化導致隨後結晶動力學的遲滯效應。溶液老化對結晶動力學的遲滯效應在PBTTT-C14/PCBM混合物具有更顯著的效果。我們還觀察到在溶液初期鑄膜PBTTT-C14和PCBM之間雙分子共晶體的形成。該特徵結構的結晶性是相對較差的，但他們可以通過隨後的加熱得到改善。而將該溶液老化後僅誘導出PBTTT的結晶，這顯示PBTTT和PCBM較不利在鄰二氯苯溶液形成共晶。

It is known that the solution structure of conjugated polymers may have great impact on the self-assembly behavior and structure in the subsequently cast film due to memory effect. In this study, we investigate the effect of aging the solution on the crystallization kinetics of P3HT and PBTTT-C14 in the subsequently cast film. P3HT was dissolved in chlorobenzene (CB) and tetrahydrofuran (THF), where CB is a better solvent than THF, to form macroscopically homogeneous solutions. The resultant solutions were then allowed to age for different time periods at room temperature up to two weeks. It was found that the crystallization kinetics of P3HT in the film cast from CB was essentially unperturbed by the solution aging. On the other hand, the solution aging exerted an obvious influence on the crystallization rate of P3HT in the THF-cast film, where the film cast from the solution aged for longer time exhibited a lower initial crystallinity and slower crystallization rate. The retardation of the crystallization kinetics was attribute to the development of the nanowhisker structure in the solution in the aging process. In the case of CB solution, the development of such a morphological entity by P3HT crystallization during aging was minor, such that the crystallization occurred in an essentially homogeneous amorphous matrix in the film. In the case of THF solution, the nanowhiskers formed during the aging due to poorer solvent quality and these whiskers were transferred into the film. The nanowhisker entity remained stable even in the melt state and thus imposed a topological constraint to the subsequent crystallization upon cooling. In this case, the crystallization of P3HT took place in the mesh regions constrained by the networking of the naowhiskers, so as to retard the crystallization kinetics.
In the case of PBTTT-C14, the film was cast from its solution with dichlorobenzene. It was found that solution aging led to a weak retardation of the crystallization kinetics in the subsequently cast film. The effect of solution aging on reducing the crystallization kinetics amplified significantly in PBTTT-C14/PCBM blends. We also observed the formation of bimolecule crystal between PBTTT-C14 and PCBM in the fresh solution-cast film. The crystallinity and crystalline order of this characteristic structure was relatively poor, but they could be improved by the subsequent heating. The solution aging induce the crystallization of PBTTT only, indicating that the PBTTT and PCBM did not prefer to cocrysatllize in the solution with dichlorobenzene.

Table of contents
Abstract III
Table of contents V
List of Figures VII
List of Tables IX
Chapter 1 Introduction 1
1.1 Background 1
1.2 Characteristics of the organic polymer material 2
1.2 Crystallization of polymer 4
1.3 Polymer:Fullerene Intermolecular Interactions 5
1.4 Influence of aging and gelation processes in conjugated polymers 6
1.5 Solvent effect in Conjugated Polymers 8
1.6 Motivation 10
Chapter 2 Experimental Section 12
2.1 Materials 12
2.2 Sample Preparation 13
2.3 Differential Scanning Calorimetry (DSC) Measurements 13
2.4 Transmission electron microscopy (TEM) observation 13
Chapter3 Results and Discussion 14
3.1 Solution structure and phase transition behavior of P3HT cast films 14
3.2.1 Intercalation structure of the PBTTT cast films 26
3.2.2 Aging effect of the PBTTT cast films 30
Chapter 4 Reference 45

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