[en] The nanoscopic morphology of soft material thin films such as plastic, elastomer and rubber films has been successfully analyzed by grazing-incidence small-angle X-ray scattering (GISAXS). Recently, advanced GISAXS techniques for analysis for surface-, volume-, and material (element)-sensitive method has been reported. Resonant (anomalous) GISAXS and GISAXS with low X-ray photon energy (tender X-rays and soft X-rays near K-edge of carbon) allows probing a complex nanomorphology with those sensitivity. In this report, principle of GISAXS will be outlined simply and advanced GI-SAXS methods will be picked up to open for discussion on new possibility of structure analysis. (author)

[en] Most of soft materials form hierarchical structures and their rich varieties of mechanical properties originate from the structures and the correlation among hierarchies. Here we discuss how we can analyze the hierarchical structures in soft materials by using the combination of various scattering methods. We describe the features of each scattering method briefly and show the examples of the analyses of soft materials with the combined scattering methods. (author)

[en] Small-angle neutron scattering was employed in order to perform a real time and in-situ observation on a polymerization-induced self-assembly process in in-vivo or in-vitro systems; precise living anionic polymerization of poly-styrene-b-polyisoprene, pre-irradiation radical polymerization of polystyrene onto a polytetrafluoroethylene film, and microbial or enzymatic polymerization of cellulose. The aim of these studies is to clarify self-organizations of macro-molecular assemblies appeared in open non-equilibrium systems, which are exposed to external energy and mass flows induced by chemical reactions. The open non-equilibrium systems are believed to be important for understanding pattern formations not only in materials processing in industry but also in living things. Small-angle scattering observed for the systems was investigated according to the methods established for condensed matter physics (fractal and computational analyses), bridging with synthetic chemistry and molecular biology. (author)

[en] The polymer layers adsorbed on carbon black (CB) aggregates in rubber/CB systems have been investigated with contrast variation small-angle neutron scattering (SANS) method. Specimens were swollen by toluene/deuterated toluene solvents having various scattering length densities and their scattering intensities were measured with SANS. The contrast variation SANS for the specimens yielded partial scattering functions: the scattering function for polymer-polymer correlation S_pp(q), the scattering function for CB- CB correlation S_cc(q), and the scattering function for polymer- CB correlation S_pc(q). The analyses of the partial scattering functions explored the existence of dense polymer layers around CB aggregates. Several characteristic parameters are estimated from the analyses, such as the size of aggregates, the thickness of layers, and the volume fractions of polymer of layers and matrix. (author)

[en] Many nuclear power plants are in the planning stage throughout the world today, as the fossil power plants utilizing coal or petroleum are restrained because of world energy and environmental aspect. And furthermore, nuclear power plants are now strongly expected to be safer and more reliable operation. From the view point of preventing faculty failure, it is very important to manage the preservation of aged polymers that are used in many components as domestic nuclear power plants prolonged their operation years. This paper reviews some results of confirmation tests and ways of quality management for the functional rubber and plastic materials that are used in several components of nuclear power plants. (author)

[en] Ibaraki University developed the novel neutron microscope on the instrument iMATERIA at MLF of J-PARC, which was originally a powder diffractometer, recently reinforced by detecting small-angle scattering. The method of dynamic nuclear polarization (DNP) for protons was combined with small angle neutron scattering (SANS) (DNP-SANS). In a long course of history of DNP, our activity is the world's first challenge to incorporate DNP-SANS for routine industry uses. This 'neutron microscope' provides us multiple reciprocal space images by changing scattering lengths of proton, in turn by varying 'contrast' of individual scattering components. Conventionally, for the contrast variation, chemical treatments are required to substitute protons with deuterons. The DNP approach is suitable for industry application (for example to observe tire rubbers), because we do not need highly-specialized deuterium substitution. In this article, we describe theoretical background of DNP including scattering functions and the experimental of 7T super-conductive magnet, NMR to evaluate proton spin polarization, and microwave to change polarization. The sample preparation to dope radicals into sample specimens are necessary. We review the studies on homopolymers of polystyrene and polyethylene, poly (styrene-b-isoprene) diblock copolymer, and vulcanized SBR rubber. (author)

[en] Nine kinds of ethylene-propylene-diene elastomer (EPDM) were irradiated under low dose rate (0.33 kGy/h) at room temperature that is the reference condition. As the short time irradiation condition, two conditions shown below were studied. 1) Irradiation of 4.2 kGy/h in 0.5 MPa oxygen at room temperature. 2) Irradiation of 5.0 kGy/h in air at 70degC. It was found out that two methods mentioned above were available as time accelerated irradiation conditions on the view point of changes in mechanical properties. Heat resistant fluorine-containing elastomer did not have radiation resistance. The compounding of EPDM for heat resistance did not have radiation resistance. There was no correlation between heat resistance and radiation resistance. The synergistic relationship between heat and radiation was found out and the coefficient of synergism was proposed to express the degree of synergism. The energy transfer from polymer to antioxidant reagent during irradiation has an important role in radiation induced degradation of elastomers. (author)

[en] We developed a thermoplastic elastomer by blending symmetric polystyrene-block-polyisoprene-block-polystyrene (SIS) and asymmetric SIS block copolymer. This polymer blend is promising as an elastic film because it has superior physical properties, such as high modulus and recoverability, compared to symmetrical SIS homopolymers which have been used as adhesives. In order to elucidate the reasons for such excellent physical properties, its structure was investigated by time-resolved small angle X-ray scattering, transmission electron microscope observation, and SCF simulation in stretching process. In the film made by pressing close to industrial processing, the characteristic structural change of the styrene domain was observed with time-resolved small angle X-ray scattering. Furthermore, it was also found that the processing conditions have a strong influence on the phase separation structure. (author)

[en] An abstract of the radiation process of polymer materials and the polymer reaction by radiation is explained. Main radiation is 250 keV to 10 MeV of electron rays in the industry. Radiation cross-linked rubber has less the tensile strength than that by sulfur and organic peroxide crosslinking. The main origins of low tensile strength are caused by cut of backbone chain and ozone depend on radiation. Acceleration of crosslinking and short time of radiation are necessary to improve these defects. To accelerate crosslinking, we used crosslinking accelerators, for example, three poly-functional monomers (PFM). The maximum tensile strength of styrene-butadiene rubber (SBR) not added crosslinking accelerators showed 3 MPa at 110 kGy, but SBR added A-TMMT (tetramethylolmethane tetraacrylate) showed 5.5 MPa at 110 kGy. Radiation crosslinking of many kinds of rubber: isoprene (IR), SBR, CR, nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), butyl rubber (IIR), chlorinated butyl rubber (CIIR), EPM and TPE are explained. (S.Y.)

[en] Usefulness of recent synchrotron X-ray-absorption fine structure (XAFS) measurements is described for characterization of network structures of vulcanizates. The first example is related to the formation of two-phase network morphology in vulcanizates. In situ zinc K-shell X-ray-absorption near-edge structure (XANES) measurement during vulcanization is reported to support the simultaneous progress of two sulfur cross-linking reactions in the N-(1,3-benzothiazol-2-ylsulfanyl) cyclohexanamine accelerated systems under the presence of ZnO or zinc stearate. The second is a study on in situ zinc K-shell XAFS measurement for analyzing a novel intermediate, which was generated from ZnO and stearic acid during vulcanization. The intermediate [Zn₂ (μ-O₂CC₁₇H₃₅)₂]²⁺(OH^-)₂ is newly found as an active catalyst for the sulfur cross-linking reaction. The third is a study on sulfur K-shell XANES measurement to determine characteristics of sulfidic linkages in vulcanizates which were prepared by the accelerated vulcanizations using the new intermediate. The disulfidic linkage is reported to be dominantly generated in the systems. Finally, a study on scanning transmission X-ray microscopy, which provides the XANES spectra in 2D mapping, is introduced. The XAFS analysis may be a powerful tool for characterization of rubber materials. (author)