Interfacial cross-link inhomogeneity of a phenolic resin on a silica surface as revealed by X-ray and neutron reflection measurements

Izumi, Atsushi*; Shudo, Yasuyuki*; Shibayama, Mitsuhiro*; Yoshida, Tessei*; Miyata, Noboru*; Miyazaki, Tsukasa*; Aoki, Hiroyuki

Macromolecules, 53(10), p.4082 - 4089, 2020/05

https://doi.org/10.1021/acs.macromol.0c00398

Structure analysis and derivation of deformed electron density distribution of polydiacetylene giant single crystal by the combination of X-ray and neutron diffraction data

Tashiro, Koji*; Kusaka, Katsuhiro*; Hosoya, Takaaki*; Ohara, Takashi; Hanesaka, Makoto*; Yoshizawa, Yoshinori*; Yamamoto, Hiroko*; Niimura, Nobuo*; Tanaka, Ichiro*; Kurihara, Kazuo*; et al.

Macromolecules, 51(11), p.3911 - 3922, 2018/06

https://doi.org/10.1021/acs.macromol.8b00650

Photonic crystals fabricated by block copolymerization-induced microphase separation

Motokawa, Ryuhei; Taniguchi, Tatsuo*; Kumada, Takayuki; Iida, You*; Aoyagi, Shota*; Sasaki, Yusuke*; Kori, Michinari*; Kishikawa, Keiki*

Macromolecules, 49(16), p.6041 - 6049, 2016/08

https://doi.org/10.1021/acs.macromol.6b01190

Hierarchical structure-property relationships in graft-type fluorinated polymer electrolyte membranes using small- and ultrasmall-angle X-ray scattering analysis

Tran Duy, T.*; Sawada, Shinichi; Hasegawa, Shin; Yoshimura, Kimio; Oba, Yojiro*; Onuma, Masato*; Katsumura, Yosuke*; Maekawa, Yasunari

Macromolecules, 47(7), p.2373 - 2383, 2014/04

https://doi.org/10.1021/ma500111x

The hierarchical structures of graft-type ETFE-based polymer electrolyte membranes (ETFE-PEMs) were investigated using small- and ultrasmall-angle X-ray cattering experiments. The ETFE-PEMs with IECs 2.4 mmol/g possessed conducting graft domains around lamellar crystals, with a d-spacing of 21.8-29.1 nm, and oriented crystallites with short and long correlation distances of 218-320 and 903-1124 nm, respectively. The membranes with IECs 2.7 mmol/g showed a new phase of crystallite network domains with a d-range of 225-256 nm, indicating a phase transition from oriented crystallite to crystallite network structures in the IEC range of 2.4-2.7 mmol/g. Noted that for the ETFE-PEMs with high IECs higher conductivity at 30% RH and compatible tensile strengths at 100% RH and 80 C, compared with Nafion, originated from the well-interconnected ion channels around the crystallites and the remaining lamellar crystals and crystallites, respectively.

Small-angle neutron scattering study on specific polymerization loci induced by a copolymerization of polymerizable surfactant and styrene during miniemulsion polymerization

Motokawa, Ryuhei; Taniguchi, Tatsuo*; Sasaki, Yusuke*; Enomoto, Yuto*; Murakami, Fumiyasu*; Kasuya, Masakatsu*; Kori, Michinari*; Nakahira, Takayuki*

Macromolecules, 45(23), p.9435 - 9444, 2012/11

https://doi.org/10.1021/ma301776b

Crystal structure analysis of poly(L-lactic acid) form on the basis of the 2-dimensional wide-angle synchrotron X-ray and neutron diffraction measurements

Wasanasuk, K.*; Tashiro, Koji*; Hanesaka, Makoto*; Ohara, Takashi*; Kurihara, Kazuo; Kuroki, Ryota; Tamada, Taro; Ozeki, Tomoji*; Kanamoto, Tetsuo*

Macromolecules, 44(16), p.6441 - 6452, 2011/07

https://doi.org/10.1021/ma2006624

The crystal structure of poly(L-lactic acid) (PLLA) form has been analyzed in detail by utilizing the 2-dimensional wideangle X-ray (WAXD) and neutron diffraction (WAND) data measured for the ultradrawn sample. The WAXD data were collected using a synchrotron-sourced high-energy X-ray beam of wavelength 0.328 at SPring-8 and the WAND data were measured using a neutron beam of wavelength 1.510 with a BIX-3 detector at JRR-3, JAEA. The initial crystal structure model was extracted successfully by a direct method under the assumption of the space group 222 using about 700 X-ray reflections observed at -150C. The crystal structure model obtained by the direct method was refined so that the best agreement between the observed and calculated integrated intensities was obtained or the reliability factor () became minimal: was 18.2% at -150C and 23.2% at 25C. The obtained chain conformation took the distorted (10/3) helical form with 2 helical symmetry along the chain axis. However, the symmetrically forbidden reflections were detected in a series of the 00l reflections, requiring us to erase the 2 screw symmetry along the molecular chain. By assuming the space group symmetry 2, the structural refinement was made furthermore and the finally obtained R factor was 19.3% at -150C and 19.4% at 25C. This refined model was found to reproduce the observed reflection profiles well for all the layer lines. The X-ray-analyzed crystal structure was transferred to the WAND data analysis to determine the hydrogen atomic positions. The factor was 23.0% for the 92 observed reflections at 25C. The agreement between the observed and calculated layer line profiles was good.

Combined SANS, SEC, NMR, and UV-vis studies of simultaneous living anionic copolymerization process in a concentrated solution; Elucidation of building-up processes of molecules and their self-assemblies

Zhao, Y.; Miyamoto, Nobuyoshi*; Koizumi, Satoshi; Hashimoto, Takeji

Macromolecules, 43(6), p.2948 - 2959, 2010/04

https://doi.org/10.1021/ma902542e

Combined SANS, SEC, NMR, and UV-Vis studies of simultaneous living anionic copolymerization process; Simultaneous elucidation of propagating living chains at three different length scales

Zhao, Y.; Tanaka, Hirokazu*; Miyamoto, Nobuyoshi*; Koizumi, Satoshi; Hashimoto, Takeji

Macromolecules, 42(5), p.1739 - 1748, 2009/04

https://doi.org/10.1021/ma8017519

Theoretical modeling of associated structures in aqueous solutions of hydrophobically modified telechelic PNIPAM based on a neutron scattering study

Koga, Tsuyoshi*; Tanaka, Fumihiko*; Motokawa, Ryuhei; Koizumi, Satoshi; Winnik, F. M.*

Macromolecules, 41(23), p.9413 - 9422, 2008/11

https://doi.org/10.1021/ma800957z

On the basis of results from a small-angle neutron scattering (SANS) study of aqueous solutions of a telechelic PNIPAM with octadecyl end groups, we developed a theoretical model of the self-assembly of this polymer in water as a function of temperature and concentration. This model leads us to the following description. In solutions of concentration 10 gL kept between 10 and 20C, telechelic PNIPAMs () 22 200 gmol) associate in the form of flower micelles, containing about 12 polymer chains, assembled in a three-layered core-shell morphology with an inner core consisting of the octadecyl units, a dense inner shell consisting of partly collapsed PNIPAM chains, and an outer shell of swollen hydrated chains. Drastic changes in the scattering profile of the solution heated above 31C are attributed to the formation of mesoglobules (diameter of 40 nm) consisting of about 1000 polymer chains. On further heating, the aggregation number of the mesoglobules increases. It reaches a value of 9000 at 34C and stays constant upon further heating. In solutions of lower concentration (1 gL), association of flower micelles and mesoglobules does not occur; however, the structure of individual flower micelles and mesoglobules is not affected by the change in concentration. In solutions of 50 gL in which flower micelles are expected to be partially connected by bridge chains, a peak attributed to correlation between flower micelles appears in the scattering profiles recorded at low temperature (10-20C). In spite of the intermicellar bridging connection, the overall temperature dependence of the scattering profile at 50 gL remains similar to that at 10 gL. Distinct features of the self-assembled structures formed in aqueous telechelic PNIPAM solutions are discussed in terms of the interactions between water and the polymer main chains.

Symmetric diblock copolymer thin films on rough substrates; Microdomain periodicity in pure and blended films

Sivaniah, E.*; Matsubara, Shinya*; Zhao, Y.; Hashimoto, Takeji; Fukunaga, Kenji*; Kramer, E. J.*; Mates, T. E.*

Macromolecules, 41(7), p.2584 - 2592, 2008/04

https://doi.org/10.1021/ma702465t