10 nm Scale Cylinder-Cubic Phase Transition Induced by Caramelization in Sugar-Based Block Copolymers
10 nm Scale Cylinder-Cubic Phase Transition Induced by Caramelization in Sugar-Based Block Copolymers
复制标题
糖基嵌段共聚物中焦糖化诱导的 10 nm 尺度圆柱-立方相变
DOI：
10.1021/mz300543u
复制
发表时间：
2012
影响因子：
7.015
通讯作者：
大塚一世
中科院分区：
文献类型：
--
作者：
Y. Ouchi;S. Ueda;A. Takenaka;T. Kinumoto;T. Tsumura;M. Toyoda;磯野拓也;上田悟司，衣本太郎，津村朋樹，豊田昌宏;大塚一世
到目前为止，嵌段共聚物中微相分离的特征尺寸已经缩小到10 nm尺度。然而，形态控制这样一个小的功能仍然是一个具有挑战性的任务。本文讨论了基于低聚糖和聚（ε-己内酯）的天然/合成“混合”嵌段共聚物体系通过热退火的相变。时间分辨小角X射线散射研究表明，在10 nm尺度下，从六方密排圆柱体到体心立方的相变是温度的函数。在不同温度下退火的嵌段共聚物薄膜的原子力显微镜图像清楚地证实了这些形态的存在。这种相变（从圆柱形到立方形）的驱动力是由于热焦糖化引起的嵌段共聚物体积分数的变化。
To date, the feature size of microphase separation in block copolymers has been downsizing to 10 nm scale. However, morphological control for such a small feature is still a challenging task. The present Letter discusses a phase transition in a natural/synthetic “hybrid” block copolymer system based on an oligosaccharide and poly(ε-caprolactone) via thermal annealing. Time-resolved small-angle X-ray scattering investigation as a function of temperature indicated the phase transition from hexagonally close-packed cylinder to body-centered cubic at 10 nm scale. Atomic force microscope images of the block copolymer thin films annealed at different temperatures clearly confirmed the existence of these morphologies. The driving force of this phase transition (from cylinder to cubic) is the change of volume fraction of the block copolymer due to thermal caramelization.