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Orthorhombic Fddd Network in Diblock Copolymer Melts

Mikihito Takenaka·Tsutomu Wakada·Satoshi Akasaka·Shotaro Nishitsuji·Kenji Saijo·Hirofumi Shimizu·Hirokazu Hasegawa
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Abstract

For the first time a Fddd network structure is found in a poly(styrene-b-isoprene) (S-I) diblock copolymer melts by using small-angle X-ray scattering and transmission electron microscope, as predicted by Tyler et al. by using calculations with self-consistent field theory for diblock copolymer melts. The phase diagram of the S-I exhibits the sequence of Disorder- Fddd-Lamellae with decreasing temperature. The measured unit cell parameters ratios (a,b,c) are (1:2.02:3.46), which agrees with the result of the theoretical calculation.

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Mikihito Takenaka, Tsutomu Wakada, Satoshi Akasaka, Shotaro Nishitsuji, Kenji Saijo, Hirofumi Shimizu, Hirokazu Hasegawa. 2006-05-10. Orthorhombic Fddd Network in Diblock Copolymer Melts. https://doi.org/10.1021/ma070739u

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