Division of Multidisciplinary Chemistry– Polymer Materials Science –https://www.scl.kyoto-u.ac.jp/~polymat/index.html

Prof
TAKENAKA, Mikihito(D Eng)

Assoc Prof
OGAWA, Hiroki(D Eng)

Assist Prof
NAKANISHI, Yohei(D Sc)

Students
SEKO, Tamio (D1)
HAMAMOTO, Hiroki (D1)
ARAKAWA, Masato (M2)
NOMURA, Yuki (M2)

HARA, Yuta (M2)
KARITANI, Shu (M1)BANDO, Shunsuke (M1)
MORIMOTO, Ryuji (M1)

SHIRAISHI, Harunori (UG)
HOSOMI, Yu (UG)
SHIMABUKURO, Wataru (UG)

Scope of Research
The structure and molecular motion of polymer substances are studied, mainly using scattering methods such as X-ray,neutron, and light with intent to solve fundamentally important problems in polymer science. The main projects arestudied on 1) the morphologies and the dynamics of self-assembling processes in block copolymers, 2) the hierarchical
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Polymer Physics
Self Assembly
Hierarchical Structure

Polymer Properties
Softmatter

Recent Selected Publications
Jeon, J.; Doi, K.; Kim, H. D.; Ogawa, H.; Takenaka, M.; Ohkita, H., Correlating the Structures and Photovoltaic Properties in Phase-Separated
Blends of Conjugated Donor Polymers and Accepters, Polym. J., GRLV  Ogawa, H.; Aoki, M.; Ono, S.; Watanabe, Y.; Yamamoto, S.; Tanaka, K.; Takenaka, M., Spatial Distribution of the Network Structures in Epoxy
Resin via the MAXS-CT Method, Langmuir, 38,  Arakawa, M.; Kishimoto, M.; Nakanishi, Y.; Mita, K.; Takenaka, M., Spatial Inhomogeneity of Chain Orientation Associated with StrainInduced Density Fluctuations in Polyethylene, Polym. J., 54,  Nakanishi, Y.; Uchida, K.; Mita, K.; Kamitani, K.; Kojio, K.; Takahara, A., Morphological Study of Isotactic Polypropylene Thin Films on'L൵HUHQW6XEVWUDWHV8VLQJ*UD]LQJ,QFLGHQFH:LGH$QJOH;5D\'L൵UDFWLRQPolymer, 245,  36

TOPICS AND INTRODUCTORY COLUMNS OF LABORATORIESTopics
Spatial Inhomogeneity of Chain Orientation
Associated with Strain-Induced Density
Fluctuations in Polyethylene

Spatial Distribution of the Network
Structures in Epoxy Resin via
the MAXS-CT Method

We found the spatial inhomogeneity of chain orientationon the submicron scale in polyethylene (PE) under strain
by scanning transmission X-ray microscopy (STXM).
Strain is expected to induce the spatial inhomogeneity ofFKDLQ RULHQWDWLRQ DV ZHOO DV GHQVLW\ ÀXFWXDWLRQV DQG WKHVSDWLDOLQKRPRJHQHLW\PLJKWDOVRD൵HFWWKHPHFKDQLFDOEHhavior. However, wide-angle X-ray scattering can be used
to explore the spatially averaged local structure, and thespatial inhomogeneity of chain orientation on the submicron scale has not yet been investigated. To clarify thespatial inhomogeneity of chain orientation, we observed
QHDUHGJH ;UD\ DEVRUSWLRQ ¿QH VWUXFWXUH 1(;$)6 spectra at the carbon K-edge of stretched PE, with a resoOXWLRQRQWKHRUGHURIQPE\67;0DQGLQYHVWLJDWHG
the spatial inhomogeneity of chain orientation as well as
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revealed that the chains were more oriented in the lowdensity region under stretching. The orientation was inducedby the stretching of the polymer chains mechanically melted.

We have succeeded in visualizing the spatial heterogeneityof the reaction ratio in epoxy resins by combining mediumangle X-ray scattering (MAXS) and computed tomography(CT). The reaction ratio is proportional to the degree ofcross-linking between epoxy and amine in epoxy resins.
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toughness of epoxy resins. However, there has been nonon-destructive method to measure the spatial inhomogeneity of the reaction ratio although we can measure only
the spatially averaged reaction ratio by FT-IR. We found
WKDW WKH VFDWWHULQJ SHDN UHÀHFWHG WKH FURVVOLQNLQJ VWUXFtures in the q region of MAXS and that the peak intensity
is proportional to the reaction ratio. By reconstructing CTimages from this peak intensity, we visualized the spatial
heterogeneity of the reaction ratio. The application of thismethod may not be limited to epoxy resins but may extend
to studying the heterogeneity of cross-linked structures inother materials.

Figure 1.2SWLFDOGHQVLW\LPDJHVRI+'3(DWH9FRUUHVSRQGLQJWRWKHSHDNRIWKH&±+ERQG7KHSRODUL]DWLRQGLUHFWLRQ 3' RIWKH
incident X-rays was set to be (a) parallel and (b) perpendicular to thestretching direction (MD).

Figure 2. Optical microscopy and MAXS-CT images of samples withGL൵HUHQWFURVVOLQNLQJUHDFWLRQUDWLRVLQHSR[\UHVLQICR ANNUAL REPORT, 202237