Unique toroidal morphology from composition and sequence control of triblock copolymers
Unique toroidal morphology from composition and sequence control of triblock copolymers
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DOI：
10.1021/ja050290p
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发表时间：
2005-06-22
影响因子：
15
通讯作者：
Wooley, KL
中科院分区：
文献类型：
--
作者：
Chen, ZY;Cui, HG;Wooley, KL
通过研究丙烯酸（AA）、丙烯酸甲酯（MA）和苯乙烯（S）三嵌段共聚物PAA 99-b-PMA 73-b-PS 66的组成和序列对超分子组装体形成的影响，探讨了其形成独特的环形超分子组装体的机理。在溶剂/非溶剂（四氢呋喃/水）组成范围内的实验溶液状态条件下，研究了两种三嵌段共聚物PAA 99-b-PMA 73-b-PS 66和PAA 99-b-PS 76-b-PMA 62，以及两种二嵌段共聚物PAA 99-b-PMA 155和PAA 99-b-PS 133，每种共聚物均存在2，2 ′-（亚乙二氧基）双（乙胺）。通过透射电子显微镜测定所得的形态。从具有可比长度的总疏水链段（完全PMA或完全PS）的两种二嵌段共聚物和从具有疏水（PMA和PS）段的反向连接序列的三嵌段共聚物获得环形超分子组装体的失败证明了三嵌段共聚物的独特自组装行为和嵌段共聚物序列的重要性。
The mechanism by which the unique toroidal supramolecular assemblies were formed for triblock copolymers of acrylic acid (AA), methyl acrylate (MA), and styrene (S), PAA99-b-PMA73-b-PS66, was probed in this study by investigating the influences of the block copolymer compositions and sequences. Two triblock copolymers, PAA99-b-PMA73-b-PS66and PAA99-b-PS76-b-PMA62, and two diblock copolymers, PAA99-b-PMA155and PAA99-b-PS133, were studied under experimental solution-state conditions that involved a range of solvent/nonsolvent (tetrahydrofuran/water) compositions, each in the presence of 2,2‘-(ethylenedioxy)bis(ethylamine). The resulting morphologies were determined by transmission electron microscopy. The failures to afford toroidal supramolecular assemblies from both diblock copolymers having comparable lengths of the total hydrophobic chain segment, either entirely PMA or entirely PS, and from the triblock copolymer having a reversed connection sequence for the hydrophobic (PMA and PS) segments demonstrate the unique self-assembly behaviors of triblock copolymers and the importance of the block copolymer sequence.