梳狀嵌段共聚物之階層性自組裝行為研究:接枝度效應

Self-Assembly of Supramolecular Comb-Coil Block Copolymers: Effect of Grafting Density of Comb-Block

林秋瑋(Chiu-Wei Lin)

指導教授 ： 陳信龍

國立清華大學/工學院/化學工程學系/碩士(2009年)

https://doi.org/10.6843/NTHU.2009.00265

摘要

Self-assembly block copolymer have found applications in a number of field of nanotechnology such as photonic band gap materials, nanostructure networks, nanolithographic templates, etc. Self-assembly of diblock copolymer also can
generate a series of microdomains packed in long ordered lattices, 1-D stacked lamellae, hexagonally packed cylinders, gyroid, and body-center cubic packed sphere. In this study, the self-assembly structure of a comb-coil PS-b-P4VP diblock copolymer formed by the complexation of an amphiphilic surfactant, dodecylbenzene sulfonic acid(DBSA), was investigated using SAXS and TEM. We found the large-scale PS cylindrical microdomains embedding in the matrix consisting of the small-scale lamellar mesophase organize by the P4VP(DBSA) comb block. Using the well-oriented samples prepared by LAOS, we have revealed the transitions of the hierarchical structures of PS-b-P4VP(DBSA) comb-coil diblock copolymers with respect to the overall binding fraction over a broad range of X (0.2 to 1.7). The hierarchical structure of the copolymer was found to transform from lamellae-within-lamellae to hexagonally-packed cylinder-within-lamellae to OBDD-within-lamellae and eventually to hexagonally-packed cylinder-within-lamellae.
In addition to the transformation of the larger-scale microdmnain morphology, the transformation of the orientation of the smaller-scale lamellae with respect to the larger-scale PS cylinder with increasing X was also identified. The smaller-scale lamellae displayed the edge-on arrangement at relatively low X (X <=0.5), while it transformed into the orthogonal orientation at larger X (X >=0.7). We discovered the large-scale morphology independent on bind fraction.

關鍵字

梳狀共聚物 ； 接枝度

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