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Alignment of chromosomes at the spindle equator involves two kinesin family molecular motors, Kid and CENP-E. Here, Iemura and Tanaka show differential contributions of these motors, whereby Kid promotes partial alignment before end-on microtubule attachment to chromosomes, and CENP-E promotes alignment when microtubules are stabilized.

The effects of the addition of a hyperbranched polymer (HBP) on the degradability characteristics of linear polyglycolide (PGA) fiber mats. It was revealed that HBP acted as a plasticizer, especially in underwater environments. The weight loss of the PGA fiber mats was accelerated with increasing HBP content. Considering that the structural changes in the PGA crystals depended on the feed amount of HBP, it was claimed that HBP promoted PGA degradation in both the amorphous and crystalline phases.

The conformational relaxation of ethylene-propylene-diene terpolymer (EPDM) chains at the interface with a model filler of quartz was examined by sum frequency generation (SFG) spectroscopy in conjunction with molecular dynamics (MD) simulations. We found that the glass transition temperature (T_g) of EPDM was higher at the interface than in the bulk. Also, the conformational relaxation beyond the T_g was significant for ethylene units, but not for propylene units. This information might be useful in controlling the local conformation and dynamics of polymer chains at the interface.

Sum-frequency generation (SFG) spectroscopy is a powerful tool for studying the molecular orientation in confined systems based on the second-order nonlinear optical effect. Here, we demonstrated the SFG imaging for films of uniaxially-oriented poly(vinylidene fluoride) (PVDF) and spin-coated isotactic polypropylene (iPP). The orientational difference of lamellar fibrils in the two films was identified.

Composites of fluoropolymer (FKM) and nano-carbon fillers have been considered as sealing materials for hydrogen fuel storage. We here characterize, structurally and dynamically, FKM chains adsorbed on single-walled carbon nanotubes (SWCNTs) and carbon black (CB), which were prepared by a solvent leaching method.

Poly[oligo(2-ethyl-2-oxazoline) methacrylate] (P[O(Ox)_nMA]) was mixed into a thin film of poly(methyl methacrylate) (PMMA) to construct a bioinert polymer surface in water. Near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) revealed that P[O(Ox)_nMA] having nitrogen atoms in the side chains was segregated at the outermost region of the PMMA film in a water environment. The extent of the segregation was dependent on the architecture of P[O(Ox)_nMA] due to the entropic factor, and greater extent was better for the platelet adhesion and activation.

Mechanical properties of rubber nanocomposites are believed to closely related to the chain dynamics at the interface with fillers. We here tackle this hypothesis combining traditional rheological measurements with our published results obtained by a modern technique of interfacial sensitive spectroscopy.

The aggregation states at the surface of spin-coated scaffold films composed of a multifunctional hyperbranched polymer (HBP) were characterized. While perfluorohexylethyl groups were segregated at the surface in air, the surface in water turned to be hydrophilic to minimize the free energy at the outermost region in the film. This surface reorganization was discernably faster and more remarkable for the non-annealed HBP film than for the annealed one. Fibronectin, which promoted the cellular behaviors, was more adsorbed onto the non-annealed HBP film.

A novel concept for cellular scaffolds with 2D-patterned mechanical properties was proposed. Thin films of glassy polystyrene (PS) with thicknesses ranging from 100 nm to 1 μm were prepared on epoxy resin-based line and space (L&S) patterned substrates. Although the outermost surface of PS was sufficiently flat regardless of the L&S patterned substrates, the mechanical responses differed depending on the presence of the underlying resin foundation. The initial cell adhesion and spreading and the proliferation on the scaffolds were affected by the 2D-patterned mechanical properties.

Epoxy resins, which are obtained by the curing reaction of epoxy- and amine-compounds mixture, have been often utilized in contact with metals. We herein report on the chemical composition of the epoxy resin in close proximity to the copper interface on the basis of a non-destructive method. The concentration of the amine component in the interfacial region was 2-fold higher than that in the bulk, and the interfacial enrichment extended over at least 10 nm.

Poly(lactic acid) (PLA) with titanium oxide (TiO_x) composite films were successfully prepared using a simple sol–gel method. Once TiO_x was incorporated into the PLA surface, initial cell adhesion and proliferation on the scaffolds were enhanced due to the high biocompatibility of TiO_x derivatives.

Solid-state films made from deoxyribonucleic acid where the mechanical properties are controllable, from glassy to rubbery, via semicrystalline by simply regulating the water content in the film.

The film stabilities of ω-N-(3-(dimethylamino)propyl)propylamide-terminated polystyrene (PS-N) and conventional polystyrene (PS-H) on SiO_x substrates were examined. Whereas a 20-nm-thick PS-H film was dewet at 423 K, a comparable PS-N film was stable because of the interaction between the chain end and the substrate surface. This indicates that end functionalization affects chain mobility with a relatively large scale at the solid interface.

A better understanding of the carrier formation process for semiconducting polymers, especially in thin films, is essential for designing and constructing highly-functionalized polymeric optoelectronic devices. We herein examined effects of the crystalline structure and thermal molecular motion on photo-carrier formation for melt-crystalized thin films of monodisperse poly(3-hexylthiophene) (P3HT) with various molecular weights (MWs), which were prepared from polydisperse sample by preparative chromatography.

As a surface modifier, poly[oligo(2-ethyl-2-oxazoline) methacrylate] (P[O(Ox)_nMA]) with two different degrees of polymerization (n = 7 and 19) of the side chain were mixed into poly(methyl methacrylate) (PMMA). Once the PMMA/P[O(Ox)_nMA] films contacted with water, the surface was reorganized due to the migration of P[O(Ox)_nMA]. The extent of the surface segregation was more remarkable for P[O(Ox)₇MA] than P[O(Ox)₁₉MA] due to the entropic factor, resulting that the fibroblast adhesion on the film were much better suppressed for P[O(Ox)₇MA] than P[O(Ox)₁₉MA].

A poly(4-methylpentene-1) (P4MP1) film was prepared on a quartz substrate, which was a model system of interfaces in a filler-reinforced semicrystalline polymer composite. Grazing-incidence wide-angle X-ray diffraction measurements revealed that P4MP1 in the film after the isothermal crystallization formed a Form I crystal polymorph, in which the chain axis was oriented along the direction parallel to the quartz interface. Combining sum-frequency generation vibrational spectroscopy with molecular dynamics simulation enabled us to study the local conformation of P4MP1 chains at the quartz interface and the changes that occurred with isothermal crystallization.

The interfacial dynamics of the segment of poly(methyl methacrylate) (PMMA) terminated with elemental blocks containing polyhedral oligomeric silsesquioxane (POSS), namely PPMP (PMAPOSS-b-PMMA-b-PMAPOSS), was much slower than that of the conventional PMMA. The number of platelets adhered to the PPMP film was dependent on the pre-immersion time in phosphate-buffered saline before the platelet seeding, and these results could be explained in terms of the aggregation states of water at the interface.

In the cross-sectional view of sealing gasket, the urethane sealing gasket is composed of urethane-based polymer as a matrix and heat-expandable hollow particles as independent air bubbles. The polyurethane matrix has a crosslinking structure with aliphatic diisocyanate aduct, PTMG, and bi- and trifunctional polyester pre-polymers. Not only by adjusting the mechanical properties with the blowing agent but also by being localized lubricants with talc on the surface, both excellent sealing and opening properties could be realized.