Architecture-induced phase immiscibility in a diblock/multiblock copolymer blend
Architecture-induced phase immiscibility in a diblock/multiblock copolymer blend
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二嵌段/多嵌段共聚物共混物中结构诱导的相不混溶性
DOI：
10.1021/ma9515691
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Steven D Smith
中科院分区：
文献类型：
--
作者：
R. Spontak;J. Fung;M. Braunfeld;J. Sedat;D. Agard;A. Ashraf;Steven D Smith
有序二嵌段共聚物共混物最近已成为巨大的研究兴趣的主题，因为它们可以用来阐明不同长度的嵌段的微区内分离，以及确定产生相不溶性的分子和共混物参数。在这项工作中，我们探讨了分子结构对嵌段共聚物共混物相容性的影响，通过检查两个对称的苯乙烯（S）/异戊二烯（I）嵌段共聚物的等摩尔混合物，一个SI二嵌段和其他（SI）4八嵌段。它们的分子量相同，因此嵌段长度的比率为4：1 SI：（SI）4。虽然该比例预期在二嵌段共聚物共混物中产生单相，但透射电子显微镜在此揭示，由于（SI）4共聚物的线性多嵌段结构和中间嵌段构象，二嵌段/多嵌段共混物是宏观相分离的。电子断层扫描（3D成像）允许直接可视化连接的SI和（SI）4微域在SI/（SI）4…
Ordered diblock copolymer blends have recently become the subject of tremendous research interest since they can be used to elucidate the intramicrodomain segregation of blocks differing in length, as well as to identify the molecular and blend parameters yielding phase immiscibility. In this work, we explore the influence of molecular architecture on block copolymer blend miscibility by examining an equimolar mixture of two symmetric styrene (S)/isoprene (I) block copolymers, one an SI diblock and the other an (SI)4 octablock. Their molecular weights are identical, so that the ratio of block lengths is 4:1 SI:(SI)4. While this ratio is expected to yield a single phase in diblock copolymer blends, transmission electron microscopy reveals here that the diblock/multiblock blend is macrophase-separated due to the linear multiblock architecture and midblock conformations of the (SI)4 copolymer. Electron tomography (3D imaging) permits direct visualization of connected SI and (SI)4 microdomains at the SI/(SI)4...