Seminar by Dr. Hiroshi Jinnai "Exploring structured polymeric materials with electron tomography"

This is an announcement of a seminar hosted by Quantum Wave Microscopy Unit (Shintake Unit).

Date/Time: Monday, July 29 15:30 – 16:30

Venue: Lab 1 Meeting Room D014 (Level D)

Speaker:
Dr. Hiroshi Jinnai
Leader & Research Manager, JST ERATO Takahara Soft Interfaces Project
Research Professor, Institute for Materials Chemistry and Engineering, Kyushu University

Title: Exploring structured polymeric materials with electron tomography

Abstract:
Block copolymers (BCPs) exhibit various periodic nano-scale phase-separated structures due to the immiscibility between the dissimilar sequences. In order to fabricate such structures for many applications, e.g., nanotechnology, photovoltaic devices, drug delivery etc., choice of three-deimsnional (3D) microphase separated structures and their orientation are key issues.

Recent advances in precision polymerization mean that BCP structures are becoming more complex. The identification of these complex morphologies is difficult, because conventional microscopes provide only two-dimensional (2D) transmitted or surface images of three-dimensional (3D) objects. Therefore, microscopes that are capable of capturing 3D images of nanostructures are required.

One of the BCSs, tribock terpolymers, is known to self-assemble wide variety of unique morphologies and structures. We have reported the experimental visualization of a 3D helical morphology in a polystyrene-block-polybutadiene-block-poly(methyl methacrylate) triblock terpolymer (SBM) using electron microtomography (ET).1 The ET observations revealed that the double-helical structure was composed of polybutadiene (PB) helical microdomains around hexagonal-packed polystyrene (PS) cylinder cores in a poly(methyl methacrylate) (PMMA) matrix, even though the block copolymer itself was not chiral. This helical structure may have great potential for new applications, such as templates for fabricating nanosprings or nanocoils. In such applications, orientation control of the helical structure may be necessary.

In this talk, we will demonstrate some examples of morphological studies of BCS nano-structures, including the helical one, as well as the control of their orientation. 2 We also demonstrate the significance of 3D tomographic imaging technique in such studies.

References
1.Jinnai, H.; Kaneko, T.; Matsunaga, K.; Abetz, C.; Abetz, V., Soft Matter 2009, 5, 2042.
2.Hong, S; Higuchi. T.; Sugimori, H.; Kaneko, T.; Abetz, V.; Takahara, A.; Jinnai, H. Polym. J., 2012, 44, 567.

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We look forward to seeing many of you at the seminar.

Best regards,

Reina Oshiro
Research Administrator
Quantum Wave Microscopy Unit
Phone: 098-966-8883
E-mail: reina.oshiro@oist.jp