Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Strategic design and synthesis of semiconducting polymers with intrinsic ductility and/or stretchability are introduced in this review. The best polymer films show high charge mobilities over 1 cm2V−1s−1 even at 100% tensile strain. On the other hand, their mechanical properties remain inadequate, with high elastic moduli over 0.1 GPa. For semiconducting polymers to be promising candidates in applications such as wearable electronics, electronic skins, and bioelectronics, the trade-off relationship between their electronic and mechanical performance must be prevented by further developing and combining versatile and efficient approaches.
This focused review introduces our rheological studies on static and dynamic polymer networks using Tetra gel, host-guest gel, and telechelic associative polymer networks. Although the characteristics of crosslinks strongly influence the rheological properties of polymer networks, the understanding of the molecular origin of these properties remains incomplete owing to structural complexity. Our multiple experimental characterizations, including multiaxial stretching and the combination of dynamic viscoelastic and spectroscopic measurements, will add to the molecular understanding and further provide important information on the design of novel polymer network materials.
Electrospinning (ES) is a technique that can produce nanofiber mats from arbitrary polymers. We prepared actuators consisting of nanofiber mat electrodes and ionic liquid gel using three methods, and examined the effect of the preparation method on actuator performance. The results showed that actuators with nanofiber mat electrodes spun from the lowest spinning solution concentration showed a larger strain against an applied voltage. Furthermore, we prepared two types of actuators with different fiber directions and examined the effect of nanofiber alignment on actuator performance.
Preparation and characterization of poly(2,6-dimethyl-1,4-phenylene)oxide (PPO) films exhibiting the cocrystalline phase with carvacrol, a relevant natural antimicrobial, are reported. The relative intensity and linear dichroism of two O–H out-of-plane deformation peaks (at 698 and 717 cm−1) of carvacrol can be rationalized by assuming that these peaks are due to isolated and hydrogen-bonded guest molecules, respectively, and by slower desorption of carvacrol when included as isolated molecules in the cavities of the polymer host crystalline phase.
The aggregation behaviors of a diblock copolymer and a triblock copolymer of poly(2-ethyl-2-oxazoline) (PEOX) and polyethylene oxide (PEO) in aqueous solutions were investigated mainly by static and dynamic light scattering and infrared spectroscopy. PEOX is a thermoresponsive polymer that is soluble in water at room temperature, but insoluble above 60 °C, and it forms aggregates with poly(methacrylic acid) (PMAA) by using intermolecular hydrogen bonds.
We evaluated the thermal stability of a molecularly stepped poly(methyl methacrylate) (PMMA) substrate prepared by thermal nanoimprinting and PMMA isolated chains deposited on it by in situ high-temperature atomic force microscopy. The imprinted PMMA surface and isolated PMMA chains on it could be observed at the molecular level up to the glass transition temperature (Tg) of the bulk PMMA and no significant decrease in Tg was observed. The significant thermal stability of them is unexpected and differs from our present understanding of the polymer surfaces.
The thin film structures and tribological properties of aqueous solutions of a silicone-based amphiphilic block copolymer confined between mica surfaces were investigated using the surface forces apparatus. Experiments were performed for three copolymer concentrations; the effect of concentration on the structures and properties was evaluated. All the concentrations exhibited good lubricity (friction coefficient on the order of 10−5). However, precise comparison between concentrations revealed some differences in the molecular friction mechanisms, which were discussed from the perspective of the dissolution states of copolymers in the solutions and adsorbed/sliding conformations.
Block co-oligomers have gained attention for fine and precise control of self-assembled nanostructures. In this study, we investigated the enzyme-catalyzed synthesis of block co-oligomers composed of cello-oligosaccharide and oligo(ethylene glycol) (OEG) chains. The propagation of cello-oligosaccharide chains from bifunctional OEG primers with d-glucose or cellobiose ends, namely, glycosyl acceptors was systematically analyzed. It was plausible from systematic characterizations that diblock and triblock co-oligomers were produced by using the respective primers.
The higher negative Seebeck coefficients (S) at 30 °C of as-received carbon nanofibers (CNFs) with respect to their polypropylene carbon nanofiber (PP/CNF) melt-mixed composites are explained by a slight electron donation from the outer graphitic shells of the CNFs to the PP molecules. Our study denotes that, contrary to expectations, insulating polymers may play a non-negligible role on the final S-values of conductive polymer composites composed of carbon-based nanostructures.
A novel superabsorbent polymer crosslinked with diacylhydrazine DC-SAP was prepared. A very-high water uptake (ca. 80,000%) was observed in DC-SAP at a crosslinking ratio of 1%. The swollen gel was instantly (<5 s) solubilized by treatment with a small amount of sodium hypochlorite solution. A commercially available bleacher could also be used for the solubilization of DC-SAP. Despite the high degradability of DC-SAP, it exhibited high chemical and thermal stability. The decomposition product is composed of pure poly(sodium acrylate), which is extremely safe substance.
We demonstrate the facile tuning of uniform Bragg reflection color from red to blue by uniaxial compression of gel films containing single-crystalline loosely packed colloidal crystals. The tuned colors can be fixed by photopolymerization of a polymer precursor solution contained in the compressed gel films.
