RESUMEN

Here, a novel method is demonstrated for the preparation of three-arm branched microporous organic nanotube networks (TAB-MONNs) based on molecular templating of three-arm branched core-shell bottlebrush copolymers and Friedel-Crafts alkylation reaction. The unique three-arm branched bottlebrush copolymers are synthesized by a combination of atom transfer radical polymerization, reversible addition-fragmentation chain transfer polymerization, and ring-opening polymerization techniques. In this approach, the length and diameter of branched tube units can be well-controlled by rational molecular design. Moreover, the as-prepared TAB-MONNs possess a high surface area and exhibit a superior adsorption capacity for Rhodamine 6G (R6G) and p-cresol.

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RESUMEN

In this paper, we report a novel method for constructing a soluble organic nanotube supported catalyst system based on single-molecule templating of core­shell bottlebrush copolymers. Various organic or metal catalysts, such as sodium prop-2-yne-1-sulfonate (SPS), 1-(2-(prop-2-yn-1-yloxy)ethyl)-1H-imidazole (PEI) and Pd(OAc)2 were anchored onto the tube walls to functionalize the organic nanotubes via copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. Depending on the 'confined effect' and the accessible cavity microenvironments of tubular structures, the organic nanotube catalysts showed high catalytic efficiency and site-isolation features. We believe that the soluble organic nanotubes will be very useful for the development of high performance catalyst systems due to their high stability of support, facile functionalization and attractive textural properties.

RESUMEN

In this paper, a novel synthesis of polyethylene glycol (PEG)-modified polypyrrole (PPy) nanomaterials is demonstrated by combining reversible addition-fragmentation chain transfer polymerization and oxidative polymerization. Dye molecules with a heat-labile linker are used as a model drug and covalently anchored onto the PEGlated PPy nanomaterials via "click chemistry." The strong absorption of such PPy nanomaterials in the near-infrared region endows the system excellent photothermal effect, which can be used not only as efficient photothermal agents for photothermal therapy but also good controllers of a drug-release system by retro D-A reaction.

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RESUMEN

A novel method for the in situ synthesis of dual-phase thermosensitive ultrasmall gold nanoparticles (USGNPs) with diameters in the range of 1-3 nm was developed by using poly(N-isopropylacrylamide)-block-poly(N-phenylethylenediamine methacrylamide) (PNIPAM-b-PNPEDMA) amphiphilic diblock copolymers as ligands. The PNPEDMA block promotes the in situ reduction of gold precursors to zero-valent gold and subsequently binds to the surface of gold nanoparticles, while PNIPAM acts as a stabilizing and thermosensitive block. The as-synthesized USGNPs stabilized by a thermosensitive PNIPAM layer exhibit a sharp, reversible, clear-opaque transition in aqueous solution between 30 and 38 °C. An unprecedented finding is that these USGNPs also show a reversible soluble-precipitate transition in nonpolar organic solvents such as chloroform at around 0 °C under acidic conditions.

RESUMEN

We demonstrate a novel method that enables the formation of core-confined bottlebrush copolymers (CCBCs) as catalyst supports. Significantly, owing to the site-isolated effect, these CCBC catalysts with the incompatible acidic para-toluenesulfonic acid (PTSA) and basic 4-(dimethylamino)pyridine (DMAP) groups can conduct a simple two-step sequential reaction in one vessel.