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The surface properties of the star polymer coating were evaluated with their resistance to protein adsorption and surface zeta (ζ)-potential to clarify the mechanism for inhibition of cell adhesion. The surface of the star polymer coating with a high density of poly(2-hydroxyethyl methacrylate) formed an electrically neutral diffuse brush structure in water and showed high resistance to protein adsorption. Considering the data obtained in the study, the surface ζ-potential and antibiofouling properties were correlated by controlling the molecular architecture of the coating material.

Surface amino groups (SAGs) on nanochitin materials were quantified using three amino-labeling reagents and two cationic dyes. After binding to SAGs, the excess labeling reagents or generated molecules were assessed by spectrophotometry. The dyes were adsorbed onto SAGs, and the excess was similarly quantified. The obtained values were compared with the titration values. Although the values by labeling reagents were underestimated, some of the values were proportional to those by titration. Reliable results were attained using the two labeling reagents with conversion equations or using Acid Orange 7 adsorption.

The morphology and physical properties of polyisoprene ionomers co-neutralized with Na⁺ and Mg²⁺ in different ratios have been studied. The mechanical and self-healing properties of the ionomer were reinforced and disturbed, respectively, at over 25 % of the Mg²⁺ ratio, where linkage via Mg²⁺ in the network is pervasive throughout the material.

We report the humidity-responsive volume changes of a poly(N-isopropylacrylamide) (PNIPAAm) gel and bending deformation of a PNIPAAm and poly(N,N-dimethylacrylamide) (PDMAAm) complex gel.

To develop a novel gel catalyst system for a selective reaction, we prepared a variety of gels with homogeneously dispersed crosslinked domain (CD) structures containing iridium complexes with various crosslinking densities. The designed CD gel catalyst catalyzed the N-alkylation of aniline with benzyl alcohol, and the steric effect of the CD structure allowed the selective formation of the secondary amine product by controlling the access of the substrate to the iridium complex.

We determined intrinsic viscosity for polystyrene (PS) samples with a wide range of molecular weight in d-limonene, which attracts interest as an environmentally friendly solvent for PS. By analyzing the experimental data obtained in d-limonene using the helical wormlike chain model with and without the excluded-volume effect, solvent quality of d-limonene for PS was quantitatively evaluated. Consequently, it was concluded that d-limonene belongs to the category of medium solvent, which is intermediate between good solvents like toluene and poor solvents like cyclohexane, for PS.

Narrow size distributions of spherical polyacrylic acid (PAA) particles are produced through precipitation polymerization without the need for stabilizers or emulsifiers. In this study, we employed small-angle X-ray scattering (SAXS) to investigate the polydispersity index (PDI) associated with the molecular weight distribution of the particles. By fitting the SAXS profiles, we were able to determine particle sizes, standard deviation, and the PDI with high precision. Our findings from SAXS confirmed that the PAA particles are monodisperse, both statistically and quantitatively, with a PDI of less than 1.05.

The isothermal crystallization behaviors of blends of cyclic polyethylene (C-PE) and linear polyethylene (L-PE) in a quiescent state were investigated. This figure shows the inverse of the half-crystallization time (1/t_1/2) as a function of the weight fraction of L-PE (Φ_L-PE) at different degrees of supercooling (ΔT). The 1/t_1/2 showed a minimum at Φ_L-PE = 30–40 wt%, irrespective of ΔT. By considering the experimental relationship between 1/t_1/2 and Φ_L-PE, we speculated that the suppression of crystallization in the blended system was caused by a novel entanglement formed by the penetration of the L-PE chain into the C-PE chain.

In this research, we reported a novel and simple approach to using tetramethylthiuram disulfide (TMTD) to prepare self-healing vulcanized natural rubber. TMTD as a sulfur donor and accelerator was used with different contents, ranging from 1.0 to 3.0 phr, to vulcanize high ammonia natural rubber (HANR). The best self-healing performance, i.e., 50–60% stress recovery and 80–95% strain recovery, was achieved for vulcanized natural rubber samples with 1.5 to 2.0 phr loading of TMTD. This approach discovered the potential application of TMTD in preparing self-healing vulcanized natural rubber.

In this paper, the construction of a hierarchical supramolecular structure comprising reduction-responsive DNA microspheres and semi-artificial glycopeptide-based micro-asters was described. Such a unique hierarchical supramolecular structure was obtained through molecular assembly of three oligonucleotides and a semi-artificial glycopeptide in a single thermal annealing process under aqueous conditions in the presence of Mg²⁺.

Atomic molecular dynamics simulations of the complexation of plasmid DNA in the presence of two types of cationic peptides clear the mechanism of plasmid DNA condensation for gene delivery systems.

Quantifying the interfacial energy of a polymer–liquid interface is challenging. We previously succeeded in analyzing the interfacial energy of a dynamic polymer brush interface by measuring the deformation of an ultrathin elastomer film floating on water. However, the quantitativity remains debatable because the bulk modulus was used. In this study, we reanalyze the interfacial energy using the ultrathin-film modulus. Large negative interfacial energy was observed for the system of high-density stretched brushes. The free energy balance for the system floating on water was calculated, validating the negative interfacial energy.

Two types of polyimide nanofibers (PINFs) were prepared. PINF-I (lengths = 305 ± 152 nm and diameters = 12 ± 2 nm) was prepared via crystallization of PI dissolved in a concentrated sulfuric acid solution. Adding t-butanol to a PINF-I aqueous dispersion and subsequent freeze–drying produced PINF-II (diameters = 105 ± 99 nm) with PINF-I aggregated into a fibrous form. The PI crystalline unit cell parameters were orthorhombic, a = 1.21 nm, b = 0.88 nm, and c = 2.23 nm (molecular chain axis direction).

PVDF forms β- and γ-phases in the presence of alkylammonium salts. We investigated crystal polymorphism obtained by various crystallization processes using FT-IR in PVDF added with two different alkylammonium salts. The fractions of crystalline phase changed with crystallization processes and ionic salts, which is attributed to the different crystallization mechanisms depending on the strengths of the ion-dipole interactions between alkylammonium salts and PVDF chains.

A PS/silica hybrid nanomatrix was formed by graft copolymerization of first styrene and then VTES onto NR particles in the latex stage. This hybrid nanomatrix structure was composed of nanosilica with a size of less than 100 nm and PS, which resulted in outstanding mechanical and viscoelastic properties. The superior properties of the hybrid nanomatrix were due to the synergetic effect of PS and nanosilica. The morphology and mechanical properties of the hybrid nanomatrix were maintained after acetone extraction, whereas they were distorted and reduced, respectively, after annealing

Polytetrafluoroethylene (PTFE) has widely been used in essential daily items and biomedical materials. The application range of PTFE should be greatly expanded if it can be flexibly functionalized. However, the functionalization method is still limited. In this study, peptides with affinity to PTFE were identified through affinity-based selection from a phage-displayed peptide library. The peptides had potential as a molecular glue to immobilize functional proteins and biomolecular assemblies, i.e., phages, onto PTFE films.

The new strategy of two different AS-ODNs (targeting K-ras and YB-1) being delivered simultaneously to the same target cancer cell was investigated using the quantized complex made from AS-ODNs and short β-glucan (schizophyllan (SPG)). We used the quantized complex properties to prepare both end complexes with AS-ODNs on both ends. Both end complexes silenced two target genes and showed high inhibition of cancer cell growth. The results indicate that both end complexes can deliver two antisense sequences at the same time and show a synergistic effect.

We investigated stereospecific copolymerization of styrene with p-divinylbenzene (DVB) using an aryl-substituted [OSSO]-type zirconium(IV) precatalyst with dried modified-methylaluminoxane (dMMAO) as an activator. The resulting poly(iso-styrene‐co‐DVB)s possessed very high molecular weights (M_w = 93,000−131,000 g mol⁻¹) and unimodal polydispersity indices (PDI = 1.8−2.5). The DVB contents (7–20 mol %) in the copolymer could be varied depending upon the feed concentration. These copolymers exhibited an amorphous phase structure with glass transition temperatures (T_g values) of 84.8–110.9 °C.

Controlled structural color visibility was achieved using colloidal particles covered with a catechol polymer shell layer. When exposed to ammonia vapor, the pellet sample obtained by assembling the particles extended the conjugated length of the shell polymer, giving the particles the ability to absorb scattered light in situ and improving the visibility of structural colors.

Nanostructured polymer membranes were prepared from ionic liquid-crystalline (LC) monomers with taper-shaped mesogens. The virus removal properties of the ionic 1D channels prepared from a columnar (Col) LC phase were examined. In addition, as the first approach for LC membranes, the removal of several viruses from their cocktail solution by the 1D channels of Col membrane and 3D channels of bicontinuous cubic membrane was also studied.