The stiffness of conjugated polymers should lead to chain alignment near buried interfaces, even if the polymer film is nominally amorphous. Although simulations predict that this alignment layer is approximately 1.5 times the persistence length, chain alignment at buried interfaces of amorphous polymers has not been experimentally measured. Using Mueller matrix spectroscopy, the optical response of regiorandom poly(3-hexylthiophene-2,5-diyl) (P3HT) was modeled in order to extract the aligned layer thickness. By approximating the optical properties of the aligned layer as that of regioregular P3HT, the data can be effectively modeled. When the film is thicker than 150 nm, optical properties are best described with a 4-nm aligned layer, which is quantitatively consistent with previous predictions.

中文翻译：

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使用穆勒矩阵光谱法表征掩埋界面处的链排列

即使聚合物膜名义上是无定形的，共轭聚合物的刚度也应导致埋入界面附近的链排列。尽管模拟预测该排列层大约是持久长度的 1.5 倍，但尚未通过实验测量无定形聚合物埋入界面处的链排列。使用穆勒矩阵光谱，对区域随机聚（3-己基噻吩-2,5-二基）（P3HT）的光学响应进行建模，以提取对齐的层厚度。通过将对齐层的光学特性近似为区域规则 P3HT 的光学特性，可以有效地对数据进行建模。当薄膜厚度超过 150 nm 时，最好使用 4 nm 对齐层来描述光学特性，这在数量上与之前的预测一致。