研究者詳細 - 野呂　篤史

論文 - 野呂　篤史

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Stoichiometric Effects on Nanostructures of Block- and Graft-Type Supramacromolecules via Acid-Base Complexation 査読有り

Noro, A; Tamura, A; Wakao, S; Takano, A; Matsushita, Y

MACROMOLECULES 41 巻 ( 23 ) 頁： 9277 - 9283 2008年12月

担当区分：筆頭著者,　責任著者記述言語：英語出版者・発行元：Macromolecules

We report a systematic study on nanophase-separated structures from block- and graft-type supramacromolecules via acid-base complexation, where supramacromolecules are termed as supramolecules composed of a pair of macromolecules with complementary noncovalent bonding moieties. Block- or graft-type supramacromolecules were built up by blending component polymers, that is, sulfonic acid-terminated polystyrene (PS-SO3H, Mn = 19 k) or polystyrene-block-poly(4-styrenesulfonic acid) (PS-P(SSO 3H), Mn =23k) with primary amine-terminated polyisoprene (PI-NH 2, Mn = 17 k). Self-assembled nanostructures of the blends were confirmed complementarity by transmission electron microscopy and small-angle X-ray scattering. At larger acid/base molar ratio, the blends show comparatively ordered nanophase-separated structures without macrophase-separated large PS domain. Morphological transition controlled by composition has occurred in the blends of PS-P(SSO3H)/PINH2 as ordinary block copolymers show, though the blends of PS-SO3H/PI-NH2 showed macrophase separation at excess ratio of PI-NH2 to PS-SO 3H. The difference in composition dependence of morphology between two blend series is resulted from stoichiometric effects of sulfonic acid vs amine. Therefore, PS-P(SSO3H) is more useful to build up various supramacromolecular complexes with PI-NH2 than PS-SO3H just by changing the molar ratios of component polymers, that is, multiple noncovalent bonding can be found more advantageous, resulting in conforming graft-type supramacromolecules, not a block-type supramacromolecule from. PI-NH2 and PS-SO3H. © 2008 American Chemical Society.

DOI： 10.1021/ma801661c

Web of Science

Scopus

Thermoreversible supramacromolecular ion gels via hydrogen bonding 査読有り国際共著

Noro, A; Matsushita, Y; Lodge, TP

MACROMOLECULES 41 巻 ( 15 ) 頁： 5839 - 5844 2008年8月

担当区分：筆頭著者,　責任著者記述言語：英語出版者・発行元：Macromolecules

We report the thermoreversible viscoelastic properties of a supramolecular ion gel. Two building blocks were used to form "supramacromolecules". An ABA triblock copolymer (Mn = 50 000, poly(2-vinylpyridine)-b- poly(ethyl acrylate)-b-poly(2-vinylpyridine)) (P2VP-PEA-P2VP), with a mole ratio of 0.1/0.8/0.1 as a telechelic polymer, and a poly(4-hydroxystyrene) (PHS) homopolymer, with Mn = 6600 as a connector, form a physical gel via hydrogen bonding between P2VP and PHS. The thermally stable, hydrophobic ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMITFSI) provided a good solvent medium for PEA from room temperature up to at least 160°C. A solution containing 10 wt % P2VP-PEA-P2VP and 4% PHS was a liquid at elevated temperatures but on cooling formed a network at 141.5°C. Dynamic shear moduli obtained as a function of frequency at various temperatures from 30 to 160°C could be superposed to form excellent master curves, with a distinct plateau modulus extending over more than 11 orders of magnitude in frequency. The longest relaxation time inferred from the time-temperature superposition shift factors showed a similar 11 order of magnitude increase on cooling. This remarkable temperature sensitivity of the supramacromolecular ion gel is attributed to the formation of multiple hydrogen bonds between a given P2VP block and PHS cross-linker. A hydrogen bond energy of 13 kJ/mol was estimated from temperature-dependent FTIR measurements, and a straightforward analysis yielded an estimate of the number of hydrogen bonds per P2VP block as a function of temperature. This system is distinct from other supramolecular hydrogen-bonded polymers, and from hydrophobically modified associating polymers, in that below the gelation temperature the number of physical cross-links is independent of temperature, but the strength of each association, namely, the number of active hydrogen bonds within a particular cross-link site, increases strongly on cooling. © 2008 American Chemical Society.

DOI： 10.1021/ma800739c

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Scopus

Composition-dependent morphological transition of hierarchically-ordered structures formed by multiblock terpolymers 査読有り

Masuda, J; Takano, A; Suzuki, J; Nagata, Y; Noro, A; Hayashida, K; Matsushita, Y

MACROMOLECULES 40 巻 ( 11 ) 頁： 4023 - 4027 2007年5月

担当区分：筆頭著者,　責任著者記述言語：英語出版者・発行元：Macromolecules

Morphological transition of two types of multiblock terpolymers with composition has been investigated. One is undecablock terpolymers of the PISISISISIP type, while the other is hexablock terpolymers of the PISISI type, where P, I, and S denote poly(2-vinylpyridine), polyisoprene, and polystyrene, respectively. These polymer samples were prepared on the basis of anionjc polymerization method. The volume fractions of P, φp, of the former are 0.08, 0.21, 0.53, whereas those of the latter are 0.64, 0.75, and 0.87. Nanophase-separated structures were observed by TEM and SAXS, and it was confirmed that their hierarchical morphology transforms from spheres-in-lamellae structure into cylinders-in-lamellae, lamellae-in-lamella, and coaxial cylinderical structures and finally into onionlike spherical structure with increasing volume fraction of the P component. From these results, it has been found that morphological transition of multiblock terpolymers takes place obeying conventional rule, i.e., the domain shape of P component varies as sphere-cylinder-lamella-matrix as φp increases with keeping hierarchical lamellar structure from I and S. © 2007 American Chemical Society.

DOI： 10.1021/ma070155s

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Scopus

中性子反射率法による埋もれた高分子界面の構造評価招待有り査読有り

鳥飼直也、野呂篤史、松下裕秀

放射線化学 83 巻頁： 29-35 2007年3月

Neutron reflectometry on interfacial structures of the thin films of polymer and lipid 招待有り査読有り Open Access

Torikai, N; Yamada, NL; Noro, A; Harada, M; Kawaguchi, D; Takano, A; Matsushita, Y

POLYMER JOURNAL 39 巻 ( 12 ) 頁： 1238 - 1246 2007年

担当区分：筆頭著者,　責任著者記述言語：英語出版者・発行元：Polymer Journal

Neutron reflectometry is a very powerful and essential technique for the studies on material interfaces due lo its high spatial resolution, ∼a few tenths of nm, along the depth direction. The use of neutron as a probe is a big advantage for structural analysis on soft-materials, since the scattering contrast can be highly enhanced in hydrogenous materials such as polymers, surfactants, lipids, proteins, etc.. without big changes in their physical and chemical properties by substituting all or part of the hydrogen atoms in the molecules with deuterium (a deuterium labeling method). Furthermore, the neutron reflectometry can explore deeply-buried interfaces such as solid/liquid interfaces in a non-destruetive way, and make in situ measurements combined with various sample environments due to its high transmission to the materials. In this article, the neutron reflectometry is reviewed from the standpoint of researches on interfacial structures of the thin films of polymer and lipid, and its future prospects at a high-intensity pulsed-neutron source are presented. © 2007 The Society of Polymer Science.

DOI： 10.1295/polymj.PJ2007113

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Scopus

Effect of chain length and blend ratio of building blocks on nanophase-separated structures from block-type supramacromolecules via ionic interaction

Noro A., Arai S., Takano A., Matsushita Y.

Polymer Preprints, Japan 55 巻 ( 2 ) 頁： 5332 - 5333 2006年12月

担当区分：筆頭著者,　責任著者出版者・発行元：Polymer Preprints, Japan

The effect of weight fraction of building blocks on nanophase-separated structures from block-type supramacromolecules via ionic interaction was investigated. Two different end-terminated homopolymers, polystyrene terminated with sulfonic acid and polyisoprene terminated with primary amine, were prepared by using living anionic polymerizations. These two polymers were blended variously in terms of weight fraction. All blends used in this study were confirmed to show nanophase-separated structures by transmission electron microscopy and small-angle X-ray scattering, which indicates the formation of block-type supramacromolecules via ionic interaction in all blends. It has been found that simple nano-structure is formed when the polymer terminated with sulfonic acid is rich, whereas multiple nano-structures are formed when the polymer terminated with primary amine is rich.

Scopus

Neutron reflection studies on lamellar microphase-separated structures of two-component block copolymers with composition distribution 査読有り

Torikai, N; Noro, A; Okuda, M; Odamaki, F; Kawaguchi, D; Takano, A; Matsushita, Y

PHYSICA B-CONDENSED MATTER 385 巻頁： 709 - 712 2006年11月

担当区分：筆頭著者,　責任著者記述言語：英語出版者・発行元：Physica B: Condensed Matter

Segmental distribution of polystyrene blocks in lamellar microphase-separated poly(styrene-block-2-vinylpyridine) (SP) with wide composition distribution was investigated by neutron reflectivity measurements using deuterium-labeled polymers. Block copolymers with wide composition distribution were produced by mixing three monodispersed parent block copolymers, which were synthesized by an anionic polymerization method to have the same total molecular weight but with different volume fractions. The block copolymer blends whose overall S/P ratio is 0.5/0.5 were found to form a uniform lamellar structure, where lamellae were highly oriented along the direction parallel to the film surface and the interfacial thickness was evaluated as 40 Å. It was clarified that a shorter block chain in the microdomain is localized at the domain boundary, while a longer one has a peak at the center of microdomain in its segmental distribution profile. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2006.05.303

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Scopus

Chain localization and interfacial thickness in microphase-separated structures of block copolymers with variable composition distributions 査読有り

Noro, A; Okuda, M; Odamaki, F; Kawaguchi, D; Torikai, N; Takano, A; Matsushita, Y

MACROMOLECULES 39 巻 ( 22 ) 頁： 7654 - 7661 2006年10月

担当区分：筆頭著者,　責任著者記述言語：英語出版者・発行元：Macromolecules

The effect of composition distribution on microphase-separated structures of AB diblock and BAB triblock copolymers was investigated at the molecular level by measurements of neutron reflectivity. Monodispersed three poly(styrene)-d 8-block-poly(2-vinylpyridine) (DP) and three labeled triblock copolymers (PDP) and unlabeled counterparts were synthesized by a living anionic polymerization process designed to yield constant molecular weight with different volume fractions. The selective labeling method employs the blending of copolymers for a segmental distribution study while the labeled polymers are mixed for an interfacial study. Scattering length density profiles were observed by neutron reflectivity measurements for blended thin films produced by spin-coating and successive thermal annealing. It was confirmed that the blended thin films exhibit simple alternating lamellar structures, an observation consistent with the observed structures of bulk specimens. The localization phenomenon of longer and shorter block chains was also investigated. Longer block chains are generally localized at the center of the domains while the shorter block chains are localized near the domain interface as suggested by previous morphological observations. Interfacial thickness increases with an increase in composition distribution index for both diblock and triblock systems. The incremental increase for the triblock system is larger than that of the diblock system. © 2006 American Chemical Society.

DOI： 10.1021/ma061487k

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Scopus

Preparation of a block-type supramacromolecule composed of two polymers terminated with oligonucleotides

Noro A., Nagata Y., Aral S., Takano A., Matsushita Y.

Polymer Preprints, Japan 55 巻 ( 1 ) 2006年10月

担当区分：筆頭著者,　責任著者出版者・発行元：Polymer Preprints, Japan

Control of nanostructure formation from a diblock-type supramacromolecule via biocomplementary hydrogen bonding has been achieved. Two polymers used in this study are poly(4-trimethylsilylstyrene) abbreviated as PTMSS and poly(styrene-d8) as PSd8. Three complementary nucleotides were introduced into these polymers on their ends, that is, three thymidine phosphates for PTMSS and three 2'-deoxyadenosine phosphates for PSd8, using the previously developed phosphoramidite method. Association behavior in a solution was examined with NMR, and a cast bulk film obtained from a solution was confirmed to show nanophase-separated structure by TEM and SAXS. Suppression of this nanostructure formation was also attained by adding a smaller-size agent as an inhibitor.

Scopus

Nanophase-separated synchronizing structure with parallel double periodicity from an undecablock terpolymer 査読有り

Masuda, J; Takano, A; Nagata, Y; Noro, A; Matsushita, Y

PHYSICAL REVIEW LETTERS 97 巻 ( 9 ) 2006年9月

担当区分：筆頭著者,　責任著者記述言語：英語出版者・発行元：Physical Review Letters

A new nanophase-separated structure with parallel double periodicity has been identified for an undecablock terpolymer in bulk. The polymer includes two long poly(2-vinypyridine) (P) chains on each end, with five short polyisoprene (I) and four short polystyrene (S) chains at the center. This polymer exhibits a hierarchical lamellar structure with two crystallographic periods: 88 nm and 16 nm. The 88 nm period includes one thick P lamella and five thin I-S-I-S-I lamellae, of extremely high orientation. © 2006 The American Physical Society.

DOI： 10.1103/PhysRevLett.97.098301

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Scopus

PubMed

Diblock-type supramacromolecule via biocomplementary hydrogen bonding 査読有り

Noro, A; Nagata, Y; Takano, A; Matsushita, Y

BIOMACROMOLECULES 7 巻 ( 6 ) 頁： 1696 - 1699 2006年6月

担当区分：筆頭著者,　責任著者記述言語：英語出版者・発行元：Biomacromolecules

Control of nanostructure formation by a diblock-type supramacromolecule via biocomplementary hydrogen bonding has been achieved. Two different homopolymers, poly(4-trimethylsilylstyrene) and poly(styrene-d8), that are end-decorated with complementary oligonucleotides, i.e., thymidine phosphates and deoxyadenosine phosphates, were prepared by using the phosphoramidite method and blended successively. Association behavior in a blend solution was examined with NMR, and a cast bulk film obtained from the solution has been confirmed to show a nanophase-separated structure by transmission electron microscopy and X-ray scattering. Suppression of this nanostructure formation of a block-type supramacromolecule was also attained by adding a smaller agent as an inhibitor. © 2006 American Chemical Society.

DOI： 10.1021/bm0602280

Web of Science

Scopus

PubMed

Molecular design of block- and graft polymers and their nanophase-separated hierarchical structures in condensed systems 招待有り査読有り

Matsushita Y., Takano A., Torikai N., Noro A.

Kobunshi Ronbunshu 63 巻 ( 4 ) 頁： 205 - 218 2006年4月

担当区分：最終著者記述言語：日本語出版者・発行元：Kobunshi Ronbunshu

Studies on self-assembled multiphase structures of block- and graft polymers in condensed systems were reviewed. The article includes six chapters. Individual chapters are as follows: Chap. 1, Introduction; Chap. 2; history of nanophase-separated structure; Chap. 3, preparation and characterization of polymer samples; Chap. 4, morphological observations; Chap. 5; several properties; and Chap. 6, summary. The main chapter is Chap. 4. It consists of 1) morphological transition with composition, 2) domain spacing and chain dimensions of component polymers in bulk, 3) phase transition depending on external fields and microdomain interface, and 4) new hierarchical structures from newly-designed polymers. Basically amorphous polymers were treated either in glassy state or in rubbery state to avoid confusion. Amphiphilic molecules or polyelectrolytes in solutions and micelle formation of block copolymers in selective solvents were excluded due to lack of space though such fields have potential importance. Two schemes and 16 figures were used to explain research achievements and about 100 references were cited.

DOI： 10.1295/koron.63.205

Scopus

Preparation and characterization of a styrene-isoprene undecablock copolymer and its hierarchical microdomain structure in bulk 査読有り

Nagata, Y.; Masuda, J.; Noro, A.; Cho, D. Y.; Takano, A.; Matsushita, Y.

Macromolecules 38 巻頁： 10220-10225 2005年11月

A mesoscopic Archimedean tiling having a new complexity in an ABC star polymer 査読有り

Takano, A.; Kawashima, W.; Noro, A.; Isono, Y.; Tanaka, N.; Dotera, T.; Matsushita, Y.

JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS 43 巻頁： 2427-2432 2005年9月

Novel synthesis and characterization of bioconjugate block copolymers having oligonucleotides 査読有り

Noro, A.; Nagata, Y.; Tsukamoto, M.; Hayakawa, Y.; Takano, A.; Matsushita, Y.

Biomacromolecules 6 巻頁： 2328-2333 2005年7月

Effect of molecular weight distribution on microphase-separated structures from block copolymers 査読有り

Noro, A.; Cho, D.; Takano, A.; Matsushita, Y.

Macromolecules 38 巻頁： 4371-4376 2005年5月

TGIC separation of PS-b-P2VP diblock and P2VP-b-PS-b-P2VP triblock copolymers according to chemical composition 査読有り

Cho, D.H..; Noro, A.; Takano, A.; Matsushita, Y.

Macromoleules 38 巻頁： 3033-3036 2005年4月

Effect of composition distribution on microphase-separated structure from BAB triblock copolymers 査読有り

Noro, A.; Iinuma, M.; Suzuki, J.; Takano, A.; Matsushita, Y.

Macromolecules 37 巻頁： 3804-3808 2004年5月

Effect of Composition Distribution on Microphase-Separated Structure from Diblock Copolymers 査読有り

Y. Matsushita, A. Noro, M. Iinuma, J. Suzuki, H. Ohtani, A. Takano

Macromolecules 36 巻頁： 8074-8077 2003年

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