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.
Distribution of end of polymer in the filler-filled material is simulated using self-consistent field method. In our simulation results, the segregation of ends of polymer can be found at the interface of filler, though the depletion region of ends is also existed around the region in the distance of Rg from filler. Sizes and shape of filler are affected to the segregation of ends of polymer, and in the cases of smaller or spherical fillers, the density of ends of polymer near the interface of filler increases. These results can be explained by the entropic effect of polymer chain ends. The segregation of ends contributes to the stabilization of interface of filler adding the entropic part of free energy.
Drug loading and release abilities of freestanding films made of polyion complexes of chondroitin sulfate C and chitosan were examined using dye molecules such as methylene blue and carboxyfluorescein. The dye-loading films were prepared using pre- and post-loading methods. Microscopic film morphologies were not affected by the dye loadings. The mechanical strengths of the dye-loaded films were almost identical to those of the unloaded films. The dye release behaviors of the films in various aqueous solutions were examined, and the results demonstrated that the films exhibited media-responsive dye release abilities.
Silicon- and carbon-bridged polythiophenes, dithienosilole (DTS) and cyclopentadithiophene (DTC) homopolymers with 2-ethylhexyl or n-octyl substituents on the bridging atom, were synthesized and their optical and electrochemical properties were investigated. OFET devices containing the present polymer films as the active layers were fabricated to investigate their carrier transport properties. The device based on a DTS polymer with n-octyl substituents showed much higher carrier mobility than that of the DTC polymer with the same substituents.
Artificial sheet-like nanocelluloses composed of cellulose oligomers with the cellulose II allomorph were synthesized by phosphorylase-catalyzed enzymatic reactions, and their hydrolytic activities against ester substrates were characterized. The as-prepared nanocelluloses exhibited relatively low hydrolytic activities. However, distorted and smaller nanocelluloses with larger surface areas, which were prepared by sonication-based mechanical treatment of the as-prepared nanocelluloses, exhibited significantly greater hydrolytic activities.
The wrapping abilities of comb-like polymers with pendant conjugated fluorine moieties and their tunable electrical properties of SWNTs were discussed. It is found that longer side-chain-conjugated fluorene segments in homopolymer (P(St-Fl)300, 7) can strongly bind to the SWNTs surfaces through π–π interaction and its copolymer (P2VP79-co-P(St-Fl)347, 5a) lead to predominant dispersion of SWNTs due to the flexibility of P2VP for further increasing the solubility. Thus, SWNTs wrapped by 5a after thermal annealing can be selected as a gate electrode, whereas the spin-coated SWNTs wrapped by 7 can be as a semiconductor for the FET channel, resulting in a mobility of 0.82 cm2 V−1s−1, a threshold voltage of 0.35 V and an ON/OFF ratio of 2.8 × 104.
The cloud point was determined in aqueous poly(N,N-diethylacrylamide) (PDEA) solutions. It was found that the cloud-point curve of each PDEA sample has a critical point and each PDEA solution exhibits phase separation into two liquid phases when the temperature is increased above its cloud point, which has not been previously observed for aqueous poly(N-isopropylacrylamide) (PNIPA) solutions. Therefore, the aqueous PDEA solutions exhibit typical phase behavior of lower critical solution temperature type, which is substantially different from that observed for PNIPA.
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.
