Morphology and Thermodynamic Properties of a Copolymer with an Electronically Conducting Block: Poly(3-ethylhexylthiophene)-block-poly(ethylene oxide)

详细信息    查看全文

• 作者：Shrayesh N. Patel ; Anna E. Javier ; Keith M. Beers ; John A. Pople ; Victor Ho ; Rachel A. Segalman ; Nitash P. Balsara
• 刊名：Nano Letters
• 出版年：2012
• 出版时间：September 12, 2012
• 年：2012
• 卷：12
• 期：9
• 页码：4901-4906
• 全文大小：343K
• 年卷期：v.12,no.9(September 12, 2012)
• ISSN：1530-6992

文摘

We report on the synthesis and morphology of a block copolymer, poly(3-(2鈥?ethylhexyl)thiophene)-b-poly(ethylene oxide) (P3EHT-b-PEO), that conducts both electrons and ions. We show that in the melt state the P3EHT-b-PEO chains self-assemble to produce traditional nanoscale morphologies such as lamellae and gyroid. This is in contrast to a majority of previous studies on copolymers with electronically conducting blocks wherein a nanofibrillar morphology is obtained. Our approach enables estimation of the Flory鈥揌uggins interaction parameter, 蠂. The segregation strength between the two blocks is controlled through the addition of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). For the salt-free sample, the gyroid morphology, obtained in the melt state, is transformed into lamellae below the melting temperature of the P3EHT block. This is due to the 鈥渂reaking out鈥?of the crystalline phase. For the salt-containing sample, P3EHT-b-PEO has a lamellar morphology in both melt and crystalline states (confined crystallization).

Keywords:

<a id="authors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=Conducting+polymers&qsSearchArea=searchText">Conducting polymers; <a id="authors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=semicrystalline+block+copolymer&qsSearchArea=searchText">semicrystalline block copolymer; <a id="authors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=order%5C-to%5C-disorder+transition&qsSearchArea=searchText">order-to-disorder transition; <a id="authors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=confined+crystallization&qsSearchArea=searchText">confined crystallization; <a id="authors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=breakout+crystallization&qsSearchArea=searchText">breakout crystallization