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Mechanochemically activated graphite (Gp) and iron particle surfaces were prepared, and the Gp/iron composite interfaces were elucidated to utilize new functions. Activated iron particles with the oxygen atoms prepared by a milling under oxygen atmosphere were shown. Alternately, the Gp particles activated by the milling under argon atmosphere easily agglomerated because of the dangling bonds on the edge surfaces. In the composites, the interfacial bonds (e.g., Fe–O–C) between the Gp and iron oxides on the iron were clearly induced while preserving the carbon atom six-ring structures. Furthermore, the molecular orbital calculations suggested that the activated oxygen atoms in the iron oxides effectively abstract hydrogen atoms from the C–H groups of the Gp edge, resulting in the active bare carbon atoms which can form the interfacial bonds; therefore, the interfacial Fe–O–C bonds for a higher adhesive strength were successfully prepared.

Biohydrogel interpenetrated films of wooden pulp cellulose and hydroxyethyl cellulose (HEC) were prepared, and their biomedical properties were investigated. Our purpose was to obtain new material combining the nontoxicity and biocompatibility in wooden pulp cellulose films by interpenetration of HEC. It was found that the increment of HEC content affects the mechanical properties of the hydrogel from 10 to 50 wt % content of HEC. In vitro biocompatibility tests showed that protein adsorption, clotting time, and platelet adhesion were affected with the increment of HEC. All of the obtained hydrogels showed better cytocompatibility than the reference on a tissue culture grade polystyrene dish. However, HEC content seemed to decrease fibroblast cell densities due to its effect on the film properties, showing different pulp aggregation. In conclusion, the cell densities on hydrogel were significantly changed depending upon the HEC interpenetration.

Agave fibers were used to elaborate transparent and flexible cellulose hydrogel films used as a scaffold for tissue regeneration and tested by in vitro assays with NIH 3T3 fibroblast cells. Using a dimethylacetamide/lithium chloride (DMAc/LiCl) system made it possible to obtain cellulose solutions, and hydrogel films were prepared by phase inverse method without cross-linker. The concentration of LiCl in the DMAc solution was varied from 4 to 12 wt %. The resultant hydrogel films showed water contents in the range of 239–323% and enough film strength from 50 to 66 N/mm2, when the LiCl was changed from 4 to 12 wt % concentrations, respectively. The prepared agave cellulose films showed better cytocompatibility than the polystyrene dish used as control. Atomic force microscopy images showed that the hydrogel films with lower LiCl apparently contained ordered and aggregated fiber orientation. This comparison suggested that the segmental microstructure in the hydrogel films influenced fibroblast cells spreading.

Novel metal-like luster conductive films were prepared using straightforward chemical copolymerization of pyrrole (Py) and furfural (FFr). Critical parameters in the copolymerization such as monomer feed, reaction solvent, acid catalyst were studied to optimize their syntheses, film-forming properties, etc. These films showed a metal-like black luster and exhibited excellent mechanical properties with flexibility. The conjugate chemical bonds obtained from methine group were revealed in the copolymer film by Fourier transform infrared (FT-IR), ultraviolet–visible light (UV-vis), and 1H nuclear magnetic resonance (NMR) spectra. Differential scanning calorimetry (DSC) and cyclic voltammetry (CV) results implied that these copolymers showed better thermo and electrochemical stability. The density and smooth surface of the copolymer films contributed to the performance of metal-like luster, presenting the benefit of better surface reflection in the incident light.

The mechanochemical fabrication of the composites between carbon fibers (CFs) and nylon-6 (N6) was investigated using a milling process. By the milling, defected surfaces were generated on CFs to obtain the homogeneous length with preserving the cylindrical shape of CF. Fourier transform infrared spectra revealed that the band intensities due to C═O, C–N and O–H bondings increased with the milling. The band position of C–N was shifted to a higher wavenumber, while that of C═O did not change, implying that the main chain of N6 was dissociated at the C–N neighboring the C═O bonds by the force, and subsequently, new bonds between the N atoms of the activated N6 and the C atoms on CFs would be formed. Therefore, the efficient fabrication of the CF/N6 composite fibers with the interfacial bondings was achieved using the mechanochemical reaction.

The photoassisted fusion of a decanethiol-passivated Au-nanoparticle film on a glass substrate by exposure to vacuum-ultraviolet (vacuum-UV) light at 172 nm was investigated and compared to that by thermal fusion. On the basis of the thermal treatment at 200 °C, the X-ray diffraction patterns indicated that the Au-nanoparticle film with the particle diameter of 2.1 nm is completely converted to a crystalline Au film, and the film surface was coarsely granular, having a roughness of several tens of nanometers by field emission-scanning electron microscopy observation. After exposure to vacuum-UV light, the UV−vis absorption spectra revealed that the surface plasmon band at 535 nm showed a red shift with the increasing exposure time, and then the absorption band at 770 nm was clearly observed at 30 min. The diameter of the fused Au nanoparticles was larger than 20 nm on the basis of a transmission electron microscopy observation. These changes indicated that the Au nanoparticles were converted to the crysta...