Self-Assembly of All-Conjugated Poly(3-alkylthiophene) Diblock Copolymer Nanostructures from Mixed Selective Solvents
journal contributionposted on 22.06.2010 by Ming He, Lei Zhao, Jun Wang, Wei Han, Yuliang Yang, Feng Qiu, Zhiqun Lin
Any type of content formally published in an academic journal, usually following a peer-review process.
The use of mixed selective solvents provides an effective means to control self-assembly of the all-conjugated diblock copolymer poly(3-butylthiophene)-b-poly(3-hexylthiophene) (P3BHT) into nanostructured morphologies. The solvent and temperature effects on the self-assembly of P3BHT during cooling and subsequent crystallization were explored for the first time. Depending on the poor/good solvent ratio (i.e., anisole/chloroform), P3BHT chains experience different kinetic pathways, yielding nanowires at a low anisole/chloroform ratio (≤2:1), and nanorings coexisted with some nanowires at a high anisole/chloroform ratio (≥6:1). The nanowires are formed as a direct consequence of strong interchain π−π stacking, while the formation of nanorings is governed by solvophobic interactions between conjugated blocks and the poor solvent anisole to minimize the unfavorable contacts between the P3BT block (∼50 °C) and later P3HT (below 35 °C) block and anisole.