Block Copolymer Self-Assembly Involving Different Length Scales
G. ten Brinke
Groningen University, The Netherlands

1. INTRODUCTION

The presence of different length scales in block copolymer-based supramolecules and linear multiblock
copolymers results in hierarchical structure formation. Due to the comblike molecular architecture of thesupramolecules, obtained by hydrogen bonding short chain amphiphiles to one of the blocks of di- and triblock
copolymers, the short-length-scale ordered domains usually orient perpendicularly with respect to thelarge-length-scale ordering.[1] Characteristic applications of such systems exploit the straightforward
preparation of nanoporous templates by dissolving the amphiphiles after the self-assembly process. For
two-length-scale linear multiblock copolymers, where one or two long end-blocks are attached to a multiblock
consisting of relatively short diblocks, the relative orientation is usually parallel.[2]2. RESULTS
During this presentation new experimental and theoretical developments concerning the self-assembly in the above
mentioned classes of systems will be discussed. We show that in thin films of supramolecules consisting of diblock
copolymers of polystyrene (PS) and poly(4-vinyl pyridine) (P4VP), with the latter block hydrogen-bonded topentadecylphenol (PDP), PS-b-P4VP(PDP), hierarchical terrace formation is observed with the short-length-scaleorder being parallel to the large-length-scale due to the favorable interaction of PDP with substrate and freeinterface.[3] Although the PS-b-P4VP(PDP) supramolecules system, due to the presence of PDP, usually is in theintermediate segregation regime, the gyroïd morphology with P4VP(PDP) forming the continuous networks has
never been obtained despite considerable efforts. For template applications this morphology is most interestingsince the relative orientation of the domains (e.g. cylinders) with respect to the film surface plays no role. Thismorphology was finally achieved by synthesizing PtBOS-b-PS-b-P4VP triblock copolymers, containing an
additional poly(tert-butoxystyrene) (PtBOS) block. PtBOS-b-PS-b-P4VP(PDP) supramolecules with less thanstoichiometric amounts of PDP (with respect to 4VP) self-assembled in the bicontinuous double gyroid morphology
with P4VP(PDP) network channels.[4] Such systems are currently employed as templates to create nanoporous
metal actuators. In two-length-scale linear multiblock copolymers lamellar-in-lamellar self-assembly with thedifferent layers being oriented perpendicularly was recently observed by Bates and co-workers.[5] If time permits, atheoretical analysis of these kinds of systems addressing this and other aspects, e.g. the number of “thin” layers
within a “thick” layer in relation to the number of blocks of the multiblock, will be presented.[6]REFERENCES
1. Ikkala, O. and ten Brinke, G. Science, 295, 2407, (2002).
2. Masuda, J.; Takano, A.; Nagata, Y.; Noro, A.; Matsushita, Y. Phys. Rev. Lett., 97, 098301 (2006).
3. Van Zoelen, W.; Polushkin, E.; ten Brinke, G., Macromolecules 41, 8807 (2008)
4. Gobius du Sart, G. et al., Macromolecules, 43, 2970 (2010), Gobius du Sart et al., submitted.
5. Fleury, G.; Bates, F. S., Macromolecules 42, 1691 (2009).
6. Subbotin, A.; Markov, V.; ten Brinke, G., J. Phys. Chem. B, 114, 5250 (2010); Kriksin et al., to be published.

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