Electric Field Effects and Form Birefringence in Diblock Copolymers

Akira Onuki, Junichi Fukuda

Research output: Contribution to journalArticle

77 Citations (Scopus)

Abstract

We investigate effects of the electric field on diblock copolymers by assuming an induced dipolar interaction among the composition fluctuations. First, we show that, when an electric field is applied perpendicularly to lamellae, undulations start to grow if their in-plane wavenumbers are smaller than an electric wavenumber qe proportional to the field. Subsequently, the undulations grow into larger spatial structures, eventually leading to a final square-lattice pattern. Second, we calculate the Maxwell stress tensor due to the electric field to predict a finite shear modulus in a lamellar state oriented by the electric field. Third, we examine form birefringence in disordered and ordered phases. In particular, the lamellar and hexagonal phases are shown to become birefringent on spatial scales longer than the spacing of lamellae or cylinders, even if the constituent monomers are optically isotropic. This gives rise to enhancement of depolarized light scattering from lamellar microstructures, which has indeed been observed recently. Most predictions in this paper are applicable to many situations other than those in the electric field.

Original languageEnglish
Pages (from-to)8788-8795
Number of pages8
JournalMacromolecules
Volume28
Issue number26
DOIs
Publication statusPublished - Dec 1 1995
Externally publishedYes

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Electric field effects
Birefringence
Block copolymers
Electric fields
Light scattering
Tensors
Monomers
Elastic moduli
Microstructure
Chemical analysis

All Science Journal Classification (ASJC) codes

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

Cite this

Electric Field Effects and Form Birefringence in Diblock Copolymers. / Onuki, Akira; Fukuda, Junichi.

In: Macromolecules, Vol. 28, No. 26, 01.12.1995, p. 8788-8795.

Research output: Contribution to journalArticle

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