A transition from cylindrical to spherical morphology in diblock copolymer thin films

Ken Ichi Niihara, Hidekazu Sugimori, Ukyo Matsuwaki, Fumio Hirato, Hiroshi Morita, Masao Doi, Hiroyasu Masunaga, Sono Sasaki, Hiroshi Jinnai

Research output: Contribution to journalArticlepeer-review

30 Citations (Scopus)

Abstract

Microphase-separated structures in poly(styrene-block-isoprene) (SI) block copolymer thin films were investigated by transmission electron microtomography (TEMT). The SI block copolymer showed cylindrical microdomains in the bulk state. Several block copolymer thin films with different thicknesses were prepared by spin-coating and were extensively annealed before the TEMT experiments. Intriguingly, although the cylindrical morphology orienting parallel to the substrate was observed in most of the cases, spherical microdomains were found at certain film thicknesses. The thickness dependence was investigated using a computer simulation based on the self-consistent-field theory, producing a morphological phase diagram, based on minimizing free energy. We find that the distortion of the hexagonal lattice of the cylindrical microdomains caused the morphological transition to the spherical microdomains.

Original languageEnglish
Pages (from-to)9318-9325
Number of pages8
JournalMacromolecules
Volume41
Issue number23
DOIs
Publication statusPublished - 2008 Dec 9
Externally publishedYes

ASJC Scopus subject areas

  • Organic Chemistry
  • Polymers and Plastics
  • Inorganic Chemistry
  • Materials Chemistry

Fingerprint Dive into the research topics of 'A transition from cylindrical to spherical morphology in diblock copolymer thin films'. Together they form a unique fingerprint.

Cite this