Division of Chemistry for Materials, Graduate School of Engineering, Mie University, 1577 Kurimamachiya, Tsu, Mie 514-8507, Japan.
Langmuir. 2010 Dec 7;26(23):18189-93. doi: 10.1021/la1036019. Epub 2010 Oct 28.
The morphologies of Langmuir-Blodgett (LB) films of two fractionated poly(n-hexyl isocyanate) (PHIC) and those of their binary mixtures were observed by AFM, together with those of an unfractionated PHIC. The low molecular weight PHIC formed random packing of bundles consisting of rigid rods, while the high molecular weight PHIC formed random packing of bundles consisting of hairy rods. Bundle interpenetration was observed only for the latter in the semidilute regime. In the bilayer region, the area occupied by the PHIC bundles in the upper layer was obviously smaller for the high molecular weight PHIC than for the low molecular weight PHIC, suggesting that the bundles of high molecular weight PHIC more easily interpenetrate than those of low molecular weight PHIC. For the blended films composed of both low and high molecular weight PHICs, the characteristic morphologies of the respective PHIC samples were no longer present. Moreover, the morphologies of the blended films appeared to resemble each other at any molar fraction owing to the ideal miscibility of the low molecular weight and high molecular weight PHICs. The morphologies of the blended films were also similar to that of the unfractionated PHIC film in the dilute regime. In the semidilute regime, the blended films became rounded owing to an increase in bundles interpenetration between PHICs as compared to that in the dilute regime, whereas the morphology of unfractionated PHIC films remained unchanged as compared to that in the dilute regime.
通过原子力显微镜观察了两种分馏聚己基异氰酸酯（PHIC）及其二元混合物的 Langmuir-Blodgett（LB）膜的形态，以及未分馏 PHIC 的形态。低分子量 PHIC 形成了由刚性棒组成的束的无规堆积，而高分子量 PHIC 形成了由毛茸茸的棒组成的束的无规堆积。仅在后一种情况下，在半浓区观察到束的相互贯穿。在双层区域中，高分子量 PHIC 在上层中占据的 PHIC 束的面积明显小于低分子量 PHIC，这表明高分子量 PHIC 的束更容易相互贯穿，而低分子量 PHIC 的束则不容易。对于由低分子量和高分子量 PHIC 组成的混合膜，各自 PHIC 样品的特征形态不再存在。此外，由于低分子量和高分子量 PHIC 的理想混溶性，混合膜的形态在任何摩尔分数下都彼此相似。在稀相区，混合膜的形态也与未分馏 PHIC 膜相似。在半浓区，由于 PHIC 之间的束相互贯穿增加，混合膜变得圆润，而与稀相区相比，未分馏 PHIC 膜的形态保持不变。
