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The presence of visceral obesity or type 2 diabetes mellitus is a major risk factor and potential therapeutic target for non-alcoholic fatty liver disease (NAFLD). A new murine NAFLD model established in this study had obesity and insulin resistance, and rapidly develop steatohepatitis and fibrosis. This model could be useful as preclinical models for drug development of NAFLD.

Direct surface modification of polymer fibers and films by surface-initiated polymerizations has been investigated. The introduction of initiating sites on the polymer materials and successive polymerization produce surface-tethered polymer chains on the polymer surface. The surface-selective modification controls the surface properties such as wetting, lubrication and anti-fouling without sacrificing the bulk performances. Researches on grafting polymer chains to five types of polymers, poly(methyl methacrylate)-based copolymer, Br-containing polyolefins, poly(butylene terephthalate), poly(vinylidene fluoride-co-trifluoroethylene) and poly(ether-ether ketone) are reviewed.

The effect of the Molecular weight dispersity (MWD) on the interfacial width between a hPS brush and unbound dPS matrix has been investigated by NR measurement. The intermixing between hPS brush with narrow MWD and dPS matrix hardly occurred even after thermal annealing at 398 K because of dry-brush regime. In contrast, the intermixing of hPS brush with broad MWD and free dPS proceeded to increase the interfacial width like a wet-brush condition, in spite of high grafting density.

The effect of calcium ion on the swelling structure of polymer brushes bearing phosphorylcholine (PC) and cholinephosphate (CP) groups in aqueous solution were investigated by scanning probe microscopy and neutron reflectivity measurements. The CP-type polymer brushes formed collapsed structure in the aqueous CaCl₂ solution because the phosphate of CP, which is located outside the betaine unit, strongly interacts with calcium ions to form insoluble calcium phosphate. In contrast, no significant change was observed in the swollen thickness of the PC-type polymer brush in the aqueous CaCl₂ solution.

Nature-inspired material design concepts and recent progress on anti-fouling polymer materials are reviewed, and our recent researches on anti-fouling studies with polymer brushes are summarized. Zwitterionic polyelectrolyte brush immobilized surfaces represent significant anti-fouling for bio-macromolecules, oil foulants, marine fouling organisms and pipeline foulants. The anti-fouling mechanism was considered on the basis of the wetting, lubrication, hydrated chain dimension and hydrogen-bonding structure of hydrated water in the polyelectrolyte brushes.

The deviant and irregular polymerization behavior of 4-acetoxystyrene was found through the detailed study on the ATRP of various para-substituted styrenes bearing electron-withdrawing and electron-donating groups. The relationship between the rate constant for polymerization rate and the Hammett parameter was discussed.

The adhesion force between the tentacle of a live cypris and polymer brushes on the sidewall of cover glass was directly measured by scanning probe microscopy in seawater. The cypris was immobilized on the cantilever with glue, and then forced to make contact with the modified surface. When the tentacle was detached by moving the cantilever away from the surface, the torsion of the cantilever caused the laser deflection on the photodiode corresponding to the adhesion force. Polymer brush surfaces exhibited extremely low adhesion to the cypris larva.

The anti-fouling character of polymer brushes against marine organisms was investigated by performing settlement tests with barnacle cypris larvae and mussel larvae in their adhesion period, as well as a marine bacteria colonization test. The surface charge and hydration state in saline seawater appear to be important factors in the versatile anti-fouling performance of zwitterionic polyelectrolyte brushes.

The chain dimension of surface-grafted poly[3-(N-2-methacryloyloxyethyl-N,N-dimethyl)ammonatopropanesulfonate)] brush on silica nanoparticles in aqueous NaCl solution was precisely estimated by dynamic light scattering and synchrotron radiation small-angle X-ray scattering measurements to reveal large dependency on salt concentration. On the other hand, we confirmed that the chain dimension of poly(2-methacryloyloxyethyl phosphorylcholine) brush in aqueous solution was hardly affected by salt concentration.

Delaminated PS/magadiite and PPE-PS/magadiite nanocomposites were successfully prepared by a combination of surface-initiated polymerization and a melt-blending process. For a series of PS/magadiite composites, their PHRR values decreased with improvements in magadiite dispersion. Exfoliated PS/magadiite nanocomposites exhibited the lowest PHRR, forming seamless and strong solid residues.

Novel horizontal-type time-of-flight neutron reflectometer SOFIA (SOFt Interface Analyzer) was installed in BL 16 of Materials and Life Science Experimental Facility at the Japan Proton Accelerator Research Complex (J-PARC). The design and performance of SOFIA reflectometer was described based on the preliminary results of the neutron reflectivity (NR) measurements of deuterated polystyrene (d-PS) thin films, Langmuir–Blodgett film and at deuterium oxide/ polymer brush interfaces. Time-resolved in-situ NR measurement at 1-min intervals was also demonstrated to observe interfacial mixing of d-PS on the PS brush surface during annealing.

Functional non-woven fiber mats were prepared by combining the electrospinning method and surface-initiated atom transfer radical polymerization (ATRP). The surface-initiated ATRP of 3-(N-2-methacryloyloxyethyl-N,N-dimethyl) ammonatopropanesulfonate), 2-hydroxyethyl methacrylate and 2-(perfluorooctyl)ethyl acrylate proceeded successfully from the fiber surface of poly(methyl methacrylate)-co-poly(2-(2-bromoisobutyryloxy)ethyl methacrylate) without any structural changes. A grafted layer after the surface-initiated ATRP was observed by atomic force microscopy. Static contact angles against water were also evaluated to discuss the relationship between the roughness of the electrospun non-woven fiber mats and wettability.