導電高分子除了具有可撓性，同時也具有傳統高分子所沒有的導電性，能為軟性電子元件提供新穎的研究方向與應用，諸如：透明導電薄膜、有機發光二極體、太陽能電池等。導電高分子易於彎折的特性，源於柔軟的分子主幹（molecular backbone）以及弱分子間作用力（凡得瓦力），使其無法像一般金屬導體擁有規整的晶格結構，與傳統半導體材料相比通常以無序的形式堆疊，故用作元件中的導電層使用時載子容易被捕捉或散射，使元件傳導效率下降。高分子薄膜中的缺陷不僅大幅限制了應用面，也提升了製程上的難度。

為了提升薄膜製程良率，有必要了解高分子成膜過程中的分子動力學行為，本研究以導電高分子材料聚(3-己烷噻吩)（Poly (3-hexylthiophene-2,5-diyl)，P3HT）作為研究對象。透過量測變溫下的聚(3-己烷噻吩)溶液吸收峰波長位移，分析高分子從液相轉變為固相的過程中，溶液中的大聚集體（Aggregates）與小團束態（Bundle）分子的擬合結果，並透過對模擬公式的合理假設，使其可應用於分析不同溶劑、分子量的高分子溶液，將分子間作用力以量化自由度表示。

其中大分子量聚(3-己烷噻吩)縱使於良溶解率溶劑中，也無法完全溶解聚集體，故為進一步了解其在溶解過程中的分子間作用力變化，使用添加劑1,3-二碘苯（1,3-Diiodobenzene，DIB）幫助溶解。透過假設添加劑濃度對應的組態熵（Configuration entropy）變化，得到溶解效率最高的添加劑濃度，並在吸收峰波長位移與半高寬能量分佈中，皆成功體現與擬合一致的結果。

本研究以薄膜製程中的影響因素為出發點，分析溶劑溶解率、溶質分子量、溫度、添加劑濃度等參數對於分子動力學的影響，提供了對於複雜的溶液分子間作用力的有效分析方法，並為高分子液相薄膜製程提供具有可比性的量化自由度。

Semiconductor polymer thin films fabricated through solution processes often struggle to achieve good surface morphology due to the random intermolecular interactions. To improve the yield of film, it is necessary to discuss the molecular dynamics behavior during the film formation from liquid to solid phase. This study used the conjugated polymer material Poly(3-hexylthiophene-2,5-diyl) (P3HT) insights the molecular behavior of solution. By measuring and fitting the absorption peak wavelength shift of P3HT solutions under varying temperatures, obtain molecular freedom of P3HT aggregates and bundle. Considering that the fitting process might have deviation when estimating the interactions of P3HT, the quantifiable degrees of freedom for different solvents and solute molecular weights obtained by hypothesizes the influence of molecular weight on molecular interactions. Furthermore, to further investigate the manipulability of high molecular weight P3HT which is difficult to dissolve, the additive 1,3-Diiodobenzene (DIB) used to dissolve P3HT aggregates. By hypothesizing the change in configuration entropy corresponding to the additive concentration, this study successfully expected the additive concentration that achieves the highest dissolution efficiency, both wavelength shift and half-width energy distribution of absorption peak consistent with fitting results. Overall, this study insight the factors of film manufacturing processes, analyzing the influence of solvent solubility, solute molecular weight, processes temperature, and additive concentration on molecular dynamics. It provides an effective method for analyzing complex intermolecular interactions in solution and provide comparable degrees of freedom for solution-processed polymer thin films.

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