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The dispersion state of PEEK and PEI in carbon fiber-reinforced composites with a PEEK/PEI blend matrix was investigated using micro-Raman spectroscopy and scanning electron microscopy. The results revealed a continuous coexistence, on a submicron scale, of crystalline PEEK, amorphous PEEK compatible with PEI, and isolated PEI domains near the carbon fiber surface. This submicron-scale morphology accounts for the enhancement of both the glass transition temperature of PEEK and the interfacial shear strength with carbon fiber upon blending PEI with PEEK.

The molecular structure of natural rheological modifiers determines their network conformation, which mediates intermolecular interactions with emulsifiers and governs the arrangement of both components at the oil-water interface, thereby influencing emulsification performance. This thickening behavior, dictated by molecular conformation, also regulates the migration rate of emulsifiers to the interface. Furthermore, this study utilized rheological simulations to replicate the thermodynamic and kinetic conditions inherent in the emulsification process. Under a consistent set of simulation parameters, the influence of variations in modifier network conformation on the resulting droplet size distribution was systematically investigated.

Schematic illustration of tissue adhesives composed of decanoyl group-modified Alaska pollock gelatin (C10-ApGltn) and pentaerythritol poly(ethylene glycol) ether tetrasuccinimidyl glutarate (4S-PEG), and the effects of 4S-PEG molecular weight and decanoyl group modification on its physico-chemical and biological properties. The 23C10-ApGltn/4S-PEG10k adhesive showed controlled swelling, high burst strength, biodegradability, and good biocompatibility without severe inflammation, indicating its potential for cardiovascular applications.

Spin-cast polymer film formation is a nonequilibrium process controlled by competing hydrodynamic flow and solvent evaporation. By incorporating time-dependent viscosity into a spin-casting model, we identify a crossover point where hydrodynamic thinning becomes negligible. The film thickness at this crossover serves as a robust indicator of the final dried thickness, providing a unified physical framework for understanding process–structure relationships in polymer thin films.

Two new urea-containing polysilsesquioxane-based membranes were prepared. One of these membranes demonstrated impressive performance, achieving a CO₂ permeance of 4000 GPU and a CO₂/N₂ permselectivity of 13. A prediction model was generated using machine learning based on previous data to predict membrane performance. The model exhibited potential for membrane design, despite limited accuracy owing to the small number of explanatory variables used.

The origins of the excellent hydrophilicity of polyvinylpyrrolidone (PVP) were investigated using molecular dynamics simulations. The hydrations around the side chains of the constituent pentamer of PVP and its analogs and the self-associations between them were evaluated at the molecular level. In addition to the robust hydration around the side chains, the high-level suppression of self-association, originating from the well-defined chemical structure of the PVP side chain, is also a key origin of the excellent PVP hydrophilicity.

Time-resolved SAXS/WAXS reveals that nanoscale density fluctuations govern the fracture behavior of amorphous polymers. PMMA exhibits DB-type fluctuations with small amplitude that evolve into anisotropic OZD-type fluctuations under deformation. In contrast, PS shows large fractal-like fluctuations that transform into Porod-type scattering with fibrillar signatures, resulting in numerous surface crazes. These findings demonstrate that nanoscale density fluctuations govern the distinct brittle-like fracture modes of PMMA and PS.

In this study, we examined the effects of interfacial interactions on the crystallization behavior and properties of PP composites containing unmodified silica, hexamethyldisilazane (HMDS)-modified silica, and aminopropyltriethoxysilane (APTES)-modified silica. Through DMA, DSC, and DFT calculations, and mechanical testing, we demonstrated that surface functional groups strongly influence polymer–filler interactions.

Our work introduces a sustainable and highly controllable mechanochemical route for producing cellulose laurates with tunable structure and performance. Precise regulation of substitution enables tailored thermal stability and hydrophobicity, expanding design freedom for bio-based materials. The successful integration of response surface optimization highlights a robust, scalable platform for advancing next-generation cellulose-based bioplastics.

Conventional elastomers contain various geometric defects in their network structure. The model network strategy, in which well-defined precursor polymers are joined specifically at their ends, enables the reduction or control of these defects. This Focus Review highlights recent advances in understanding the structure-property relationships of model network elastomers from two viewpoints: the geometry of the polymer network and the chemical structure of the network chains. Control of these two factors opens diverse possibilities for unique and advanced properties in elastomers.

To introduce a functional group into the main chain of polystyrene, a typical vinyl polymer whose main chain consists only of carbon, radical copolymerization of styrene with a functional crosslinking monomer was carried out in the presence of a chain-transfer agent or excess initiator to avoid gelation. Main chain-functionalized polystyrene in the internally connected manner was obtained. By using diacylhydrazine, an oxidatively degradable functional group, oxidatively degradable polystyrene was obtained. This method is useful to introduce any functional group into the main chain of vinyl polymer.

This study clarifies how molecular structure governs GHz dielectric behavior in silicon-containing polyimides. Flexible polysiloxane units increase dipolar orientational polarization (P_d) and raise the dissipation factor (D_f), whereas rigid DDSQ cages suppress molecular relaxation and yield ultra-low loss. The strong linear P_d–D_f correlation demonstrates that orientational polarization is the primary factor controlling dielectric dissipation in hybrid polyimides.

Long-chain alkyl group functionalized corner-opened POSS (CO-POSS) derivatives exhibited exothermic peaks during the heating process at temperature range from 5 °C to 35 °C. Among them, C12-alkyl functionalized CO-POSS derivative with phenyl-substitution showed a cold crystallization behavior. The thermal decomposition temperature of the compounds increased with the addition of long alkyl chains, despite the higher content of flexible organic components.

Under hygrothermal conditions, the glass transition temperature of an amine-cured epoxy resin decreased over time. This decrease originated from a progressive reduction in the cross-linking density rather than from the plasticization effect of sorbed water. Degradation reactions involving scission of ether bonds occurred, producing bisphenol A and its derivatives. This bond scission was initiated by radical-mediated thermal decomposition, followed by hydrogen donation from sorbed water.

This study quantifies the relative contributions of material crystallinity and environmental factors to the marine degradation rate of poly(ε-caprolactone) (PCL). PCL sheets with controlled crystallinity were exposed at six Japanese coastal locations for 6–15 months. Machine learning regression (CatBoost, R² = 0.60) combined with SHAP analysis revealed that water temperature contributed most strongly to degradation rate variation, followed by depth and total nitrogen, while crystallinity showed moderate influence. These findings demonstrate that environmental conditions substantially drive degradation rate variability in realistic marine settings, providing insights for field-relevant material design and environmental compatibility assessment.

This review covers the gradual evolution of various catalyst transfer polymerization (CTP) methods, focusing on Kumada CTP and Suzuki-Miyaura CTP, which have notably advanced the synthesis of simple conjugated polymers (CPs) toward more complex, precisely controlled architectures. It addresses progress in other CTP methods such as Stille, Negishi, Murahashi, and Sonogashira, which are steady but gradual and significant to the discussion. It concludes by discussing the emerging field of direct arylation polymerization, which exhibits certain aspects of living polymerization behaviour, providing a sustainable and efficient pathway for synthesizing CP-based architectures.

This study constructs LGS hydrogel, LGS - E gel, and LGS/APG hydrogel systems, revealing that the formation of LGS supramolecular hydrogel relies on the synergy of hydrogen bonding and hydrophobic interaction, has a specific formation range, and exhibits dual responsiveness to temperature and pH.

The dimensional characterization of ethylcellulose (EC_x, x = 3.0 or 2.5) with a weight-averaged molar mass (M_w) of 6.32 × 10³ to 3.83 × 10⁵g mol⁻¹ and narrow dispersity (M_w/M_n < 1.22) was performed in tetrahydrofuran (THF) at 25 °C using static light scattering, small-angle X-ray scattering, and intrinsic viscosity measurements. Eleven fully substituted EC_3.0 samples were prepared by the ethylation of EC_2.5 in THF and fractionated by recycling preparative SEC in CHCl₃. Eight EC_2.5 fractions were obtained similarly. The z-averaged radius of gyration and intrinsic viscosity were measured and analyzed using a wormlike chain model. The Kuhn length, molar mass per contour length, and bead diameter were 23.1 nm, 491 g mol⁻¹ nm⁻¹, and 1.8 nm (EC_3.0) and 16.5 nm, 467 g mol⁻¹ nm⁻¹, and 1.1 nm (EC_2.5), respectively. Both are semiflexible, and x affects the global stiffness and hydrodynamic radius but not the local conformation (monomer length ≈ 0.50 nm).

Multiblock copolymers of isotactic polypropylene (iPP) and ethylene–propylene rubber (EPM) were synthesized via cross-metathesis of polyolefins containing a small number of in-chain C = C bonds. The precursor polymers were prepared with high activity using a typical isospecific zirconocene catalyst, with butadiene serving as the comonomer. Metathesis occurred at both the in-chain C = C bonds and the vinyl groups formed via 1,2-butadiene insertion, yielding long-chain-branched structures. The resulting materials exhibited significantly improved mechanical properties compared with simple iPP/EPM blends, including an approximately 50-fold increase in tensile absorption energy, demonstrating their strong potential as polyolefin-based elastomers.