Block Copolymer Assembly via Kinetic Control
Honggang Cui,1
Zhiyun Chen,2
Sheng Zhong,1
Karen L. Wooley,2*
Darrin J. Pochan1*
Block copolymers consist of two or more chemically different
polymer segments, or blocks, connected by a covalent linkage.
In solution, amphiphilic blocks can self-assemble as a result
of energetic repulsion effects between blocks. The degree of
repulsion, the lengths of the block segments, and the selectivity
of the solvent primarily control the resultant assembled morphology.
In an ideal situation, one would like to be able to alter the
morphology that forms without having to change the chemistry
of the block copolymer. Through the kinetic manipulation of
charged, amphiphilic block copolymers in solution, we are able
to generate different nanoscale structures with simple block
copolymer chemistry. The technique relies on divalent organic
counter ions and solvent mixtures to drive the organization
of the block copolymers down specific pathways into complex
one-dimensional structures. Block copolymers are increasingly
used as templating materials; thus, the ability to control the
formation of specific patterns and structures is of growing
interest and applicability.
2 Center for Materials Innovation, Department of Chemistry and Department of Radiology, Washington University in Saint Louis, Saint Louis, Missouri 63130, USA.
* To whom correspondence should be addressed. E-mail: klwooley{at}artsci.wustl.edu (K.L.W.); Pochan{at}udel.edu (D.J.P.)
