The Experts below are selected from a list of 108 Experts worldwide ranked by ideXlab platform

Ulrich Wiesner - One of the best experts on this subject based on the ideXlab platform.

  • Block Copolymer Self-Assembly Directed Hierarchically Structured Materials from Nonequilibrium Transient Laser Heating
    Macromolecules, 2019
    Co-Authors: Kwan Wee Tan, Ulrich Wiesner
    Abstract:

    We highlight two recent Approaches operating far from equilibrium for the synthesis of hierarchical porous thin film materials by coupling Block copolymer-directed self-assembly with transient laser heating. In first Block copolymer-induced writing by transient heating experiments, or B-WRITE, an all-organic Block copolymer–resols hybrid film is heated by submillisecond carbon dioxide laser irradiation, directly generating 3D mesoporous continuous resin structures and shapes. Harnessing the highly unique resin materials properties under laser heating conditions, in the second Approach Block copolymer-directed resin templating is coupled with nanosecond pulsed excimer laser annealing to generate complementary crystalline silicon nanostructures. The underlying structure formation mechanisms for such laser-induced organic and inorganic nanostructured materials are discussed, emphasizing that the nonequilibrium nature of these transient laser annealing Approaches opens up vast and new processing windows beyon...

Kwan Wee Tan - One of the best experts on this subject based on the ideXlab platform.

  • Block Copolymer Self-Assembly Directed Hierarchically Structured Materials from Nonequilibrium Transient Laser Heating
    Macromolecules, 2019
    Co-Authors: Kwan Wee Tan, Ulrich Wiesner
    Abstract:

    We highlight two recent Approaches operating far from equilibrium for the synthesis of hierarchical porous thin film materials by coupling Block copolymer-directed self-assembly with transient laser heating. In first Block copolymer-induced writing by transient heating experiments, or B-WRITE, an all-organic Block copolymer–resols hybrid film is heated by submillisecond carbon dioxide laser irradiation, directly generating 3D mesoporous continuous resin structures and shapes. Harnessing the highly unique resin materials properties under laser heating conditions, in the second Approach Block copolymer-directed resin templating is coupled with nanosecond pulsed excimer laser annealing to generate complementary crystalline silicon nanostructures. The underlying structure formation mechanisms for such laser-induced organic and inorganic nanostructured materials are discussed, emphasizing that the nonequilibrium nature of these transient laser annealing Approaches opens up vast and new processing windows beyon...

Christophe Schatz - One of the best experts on this subject based on the ideXlab platform.

  • Thermoresponsive polymer brush-functionalized magnetic manganite nanoparticles for remotely triggered drug release
    Polymer Chemistry, 2012
    Co-Authors: Stéphanie Louguet, Bérengère Rousseau, Romain Epherre, Nicolas Guidolin, Graziella Goglio, Stéphane Mornet, Etienne Duguet, Sébastien Lecommandoux, Christophe Schatz
    Abstract:

    A thermoresponsive hybrid system for drug delivery purposes is designed by modifying the surface of silica-coated magnetic lanthanum strontium manganite nanoparticles with Block copolymers following a non-covalent Approach. Block copolymers containing a short poly(L-lysine) segment and a polyether segment of varying composition are adsorbed through electrostatic interactions between positively charged lysine units and negatively charged SiO− groups at the silica surface, giving rise to mixed polyether brushes with a good control over the chain surface density and thickness of the polymer layer. The thermoresponsiveness of the assemblies is controlled by the ethylene oxide/propylene oxide ratio in the polymer brush and the corresponding LCST of the polyether Blocks. Important parameters like the aggregation temperature of the particles can be finely adjusted by modifying this ratio. The polarity of the polymer layer can also be varied to maximize the encapsulation efficiency of a moderately hydrophobic drug like doxorubicin. Drug release experiments are performed by taking advantage of the ac magnetically induced heating properties of the magnetic core to speed up the release of doxorubicin owing to structural changes within the polyether brush.

Wiesner Ulrich - One of the best experts on this subject based on the ideXlab platform.

  • Block copolymer self-assembly directed hierarchically structured materials from nonequilibrium transient laser heating
    'American Chemical Society (ACS)', 2019
    Co-Authors: Tan, Kwan Wee, Wiesner Ulrich
    Abstract:

    We highlight two recent Approaches operating far from equilibrium for the synthesis of hierarchical porous thin film materials by coupling Block copolymer-directed self-assembly with transient laser heating. In first Block copolymer-induced writing by transient heating experiments, or B-WRITE, an all-organic Block copolymer-resols hybrid film is heated by submillisecond carbon dioxide laser irradiation, directly generating 3D mesoporous continuous resin structures and shapes. Harnessing the highly unique resin materials properties under laser heating conditions, in the second Approach Block copolymer-directed resin templating is coupled with nanosecond pulsed excimer laser annealing to generate complementary crystalline silicon nanostructures. The underlying structure formation mechanisms for such laser-induced organic and inorganic nanostructured materials are discussed, emphasizing that the nonequilibrium nature of these transient laser annealing Approaches opens up vast and new processing windows beyond traditional stability limits of organic polymer materials. Finally, we highlight opportunities and challenges for possible future research directions and applications of laser-induced Block copolymer-directed hierarchical porous materials formation including structure control, materials diversification, scale-up, on-chip applications, and additive manufacturing, which may provide solutions in areas as diverse as catalysis, sensing, and energy storage and conversion.MOE (Min. of Education, S’pore)Published versio

Rudolf Zentel - One of the best experts on this subject based on the ideXlab platform.

  • liquid crystalline orientation of semiconducting nanorods in a semiconducting matrix
    Macromolecular Rapid Communications, 2008
    Co-Authors: Matthias Zorn, Rudolf Zentel
    Abstract:

    This paper describes the synthesis of narrowly distributed Block copolymers consisting of a hole conducting triarylamine Block and an anchor Block via RAFT polymerization. The anchor Block is thereby introduced via a reactive ester Approach. Block copolymers with dopamine anchor groups bind to oxidic semiconductors like TiO 2 , SnO 2 , and ZnO. Thus, it becomes possible to cover inorganic electron conducting (acceptor) nanomaterials with a corona of an organic hole conducting (donor) polymer like poly(triphenylamine), giving new hybrid materials. The poly(triphenylamine) grafted to inorganic nanorods allows the preparation of stable nanorod dispersions in appropriate solvents. At higher concentration the nanorods form liquid crystalline phases in various solvents and in a low Tg oligotriphenylamine matrix. This offers the potential to orient semiconducting inorganic nanorods in a hole conducting polymer matrix by self-assembly.