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Papers by Annette Schmidt

Research paper thumbnail of 1 Magneto-mechanical coupling of single domain particles in soft matter systems

Magnetic Hybrid-Materials

Combining inorganic magnetic particles with complex soft matrices such as liquid crystals, biolog... more Combining inorganic magnetic particles with complex soft matrices such as liquid crystals, biological fluids, gels, or elastomers, allows access to a plethora of magnetoactive effects that are useful for sensing and actuation perspectives, allowing inter alia to explore and manipulate material properties on the nanoscale. The article provides a comprehensive summary of recent advancement on employing magnetic nanoparticles either as tracers for dynamic processes, or as nanoscopic actuating units. By variation of the particle characteristics in terms of size, shape, surface functionality, and magnetic behavior, the interaction between the probe or actuator particles and their environment can be systematically tailored in wide ranges, giving insight into the relevant structure-property relationships.

Research paper thumbnail of Size effects on rotational particle diffusion in complex fluids as probed by Magnetic Particle Nanorheology

Physical Chemistry Chemical Physics

Magnetic Particle Nanorheology is a versatile tool to investigate the size-dependent rheological ... more Magnetic Particle Nanorheology is a versatile tool to investigate the size-dependent rheological properties of complex fluids using magnetic tracer particles.

Research paper thumbnail of Superparamagnetic nanoparticles with LC polymer brush shell as efficient dopants for ferronematic phases

Physical Chemistry Chemical Physics

A promising route for the fabrication of ferronematic phases is the attachment of a LC polymer sh... more A promising route for the fabrication of ferronematic phases is the attachment of a LC polymer shell onto the surface of nanoparticles. Here, we extend this approach to ferronematic phases based on superparamagnetic particles in a 5CB matrix.

Research paper thumbnail of Strain- and field-induced anisotropy in hybrid elastomers with elongated filler nanoparticles

Soft Matter

The implementation of anisotropy to functional materials is a key step towards future smart mater... more The implementation of anisotropy to functional materials is a key step towards future smart materials.

Research paper thumbnail of Scale-dependent particle diffusivity and apparent viscosity in polymer solutions as probed by dynamic magnetic nanorheology

Soft Matter

A systematic survey on magnetic particle nanorheology on polymer solutions using different partic... more A systematic survey on magnetic particle nanorheology on polymer solutions using different particle sizes and geometries, and different driving modes.

Research paper thumbnail of Creation of a PDMS Polymer Brush on SiO2-Based Nanoparticles by Surface-Initiated Ring-Opening Polymerization

Polymers

The incorporation of nanoparticles into soft matrices opens a broad spectrum of novel property co... more The incorporation of nanoparticles into soft matrices opens a broad spectrum of novel property combinations. However, one of the major challenges for these systems remains the compatibilization of particles with the surrounding matrix by proper surface functionalization. For silicon-based systems or liquid crystalline phases, polydimethylsiloxane (PDMS) brushes at the surface of particles increase the stability against particle agglomeration in such systems. Here, we report a novel approach for the functionalization of particles with a polysiloxane brush by surface-initiated ring-opening polymerization of a cyclosiloxane. For this purpose, surface hydroxy groups of silica and silica-coated hematite particles are used as initiators in combination with phosphazene bases as catalysts. The ring–chain equilibrium of a model-based solution polymerization is investigated in detail to find the appropriate reaction parameters. The corresponding molar masses are determined and compared by 1H-...

Research paper thumbnail of Soft, Wet-Chemical Synthesis of Metastable Superparamagnetic Hexagonal Close-Packed Nickel Nanoparticles in Different Ionic Liquids

Chemistry - A European Journal

Research paper thumbnail of Peptizing Mechanism at the Molecular Level of Laponite Nanoclay Gels

Research paper thumbnail of Development of an Inhalable, Stimuli-Responsive Particulate System for Delivery to Deep Lung Tissue

Colloids and Surfaces B: Biointerfaces, 2016

Research paper thumbnail of Loading of PNIPAM Based Microgels with CoFe2O4 Nanoparticles and Their Magnetic Response in Bulk and at Surfaces

The journal of physical chemistry. B, Jan 10, 2015

The present paper addresses the loading of thermoresponsive poly-N-isopropylacrylamide (PNIPAM) b... more The present paper addresses the loading of thermoresponsive poly-N-isopropylacrylamide (PNIPAM) based microgel particles with magnetic nanoparticles (MNP: CoFe2O4@PAA (PAA = poly(acrylic acid))) and their response to an external magnetic field. The MNP uptake is analyzed by transmission electron microscopy (TEM). Obviously, the charge combination of MNP and microgels plays an important role for the MNP uptake, but it does not explain the whole uptake process. The MNP uptake results in changes of size and electrophoretic mobility, which is investigated by dynamic light scattering (DLS) and a Zetasizer. The microgels loaded with MNP preserve their thermosensitivity, and they show magnetic separability and are considered as magnetic microgels. After adsorption at a surface the magnetic microgels are studied with a scanning force microscope and indentation experiments. The magnetic microgels show an elongation along the magnetic field parallel to the surface while the height of the micr...

Research paper thumbnail of A Magnetoresponsive Drug Delivery System via -Cyclodextrin Functionalized Magnetic Polymer Brushes

IEEE Transactions on Magnetics

Research paper thumbnail of Bio-inspired self-healing materials

Research paper thumbnail of We welcome our new editor-in-chief

Colloid and Polymer Science, 2015

Research paper thumbnail of Relationship between the network dynamics, supramolecular relaxation time and healing kinetics of cobalt poly(butyl acrylate) ionomers

Research paper thumbnail of Controlling the self-assembly of magnetic nanoparticles by competing dipolar and isotropic particle interactions

Journal of Colloid and Interface Science, 2014

Research paper thumbnail of Self-Healing Ionomers

From Principles to Applications, 2013

Research paper thumbnail of Magnetic Properties and Dielectrical Relaxation Dynamics in CoFe 2 O 4 @PU Nanocomposites

The Journal of Physical Chemistry C, 2011

Research paper thumbnail of One-step synthesis of functional Co nanoparticles for surface-initiated polymerization

Research paper thumbnail of Kinetic studies of surface-initiated atom transfer radical polymerization in the synthesis of magnetic fluids

Journal of Polymer Science Part A: Polymer Chemistry, 2009

Research paper thumbnail of A Magnetoresponsive Drug Delivery System via <formula formulatype="inline"><tex Notation="TeX">$\beta$</tex> </formula>-Cyclodextrin Functionalized Magnetic Polymer Brushes

IEEE Transactions on Magnetics, 2000

Research paper thumbnail of 1 Magneto-mechanical coupling of single domain particles in soft matter systems

Magnetic Hybrid-Materials

Combining inorganic magnetic particles with complex soft matrices such as liquid crystals, biolog... more Combining inorganic magnetic particles with complex soft matrices such as liquid crystals, biological fluids, gels, or elastomers, allows access to a plethora of magnetoactive effects that are useful for sensing and actuation perspectives, allowing inter alia to explore and manipulate material properties on the nanoscale. The article provides a comprehensive summary of recent advancement on employing magnetic nanoparticles either as tracers for dynamic processes, or as nanoscopic actuating units. By variation of the particle characteristics in terms of size, shape, surface functionality, and magnetic behavior, the interaction between the probe or actuator particles and their environment can be systematically tailored in wide ranges, giving insight into the relevant structure-property relationships.

Research paper thumbnail of Size effects on rotational particle diffusion in complex fluids as probed by Magnetic Particle Nanorheology

Physical Chemistry Chemical Physics

Magnetic Particle Nanorheology is a versatile tool to investigate the size-dependent rheological ... more Magnetic Particle Nanorheology is a versatile tool to investigate the size-dependent rheological properties of complex fluids using magnetic tracer particles.

Research paper thumbnail of Superparamagnetic nanoparticles with LC polymer brush shell as efficient dopants for ferronematic phases

Physical Chemistry Chemical Physics

A promising route for the fabrication of ferronematic phases is the attachment of a LC polymer sh... more A promising route for the fabrication of ferronematic phases is the attachment of a LC polymer shell onto the surface of nanoparticles. Here, we extend this approach to ferronematic phases based on superparamagnetic particles in a 5CB matrix.

Research paper thumbnail of Strain- and field-induced anisotropy in hybrid elastomers with elongated filler nanoparticles

Soft Matter

The implementation of anisotropy to functional materials is a key step towards future smart mater... more The implementation of anisotropy to functional materials is a key step towards future smart materials.

Research paper thumbnail of Scale-dependent particle diffusivity and apparent viscosity in polymer solutions as probed by dynamic magnetic nanorheology

Soft Matter

A systematic survey on magnetic particle nanorheology on polymer solutions using different partic... more A systematic survey on magnetic particle nanorheology on polymer solutions using different particle sizes and geometries, and different driving modes.

Research paper thumbnail of Creation of a PDMS Polymer Brush on SiO2-Based Nanoparticles by Surface-Initiated Ring-Opening Polymerization

Polymers

The incorporation of nanoparticles into soft matrices opens a broad spectrum of novel property co... more The incorporation of nanoparticles into soft matrices opens a broad spectrum of novel property combinations. However, one of the major challenges for these systems remains the compatibilization of particles with the surrounding matrix by proper surface functionalization. For silicon-based systems or liquid crystalline phases, polydimethylsiloxane (PDMS) brushes at the surface of particles increase the stability against particle agglomeration in such systems. Here, we report a novel approach for the functionalization of particles with a polysiloxane brush by surface-initiated ring-opening polymerization of a cyclosiloxane. For this purpose, surface hydroxy groups of silica and silica-coated hematite particles are used as initiators in combination with phosphazene bases as catalysts. The ring–chain equilibrium of a model-based solution polymerization is investigated in detail to find the appropriate reaction parameters. The corresponding molar masses are determined and compared by 1H-...

Research paper thumbnail of Soft, Wet-Chemical Synthesis of Metastable Superparamagnetic Hexagonal Close-Packed Nickel Nanoparticles in Different Ionic Liquids

Chemistry - A European Journal

Research paper thumbnail of Peptizing Mechanism at the Molecular Level of Laponite Nanoclay Gels

Research paper thumbnail of Development of an Inhalable, Stimuli-Responsive Particulate System for Delivery to Deep Lung Tissue

Colloids and Surfaces B: Biointerfaces, 2016

Research paper thumbnail of Loading of PNIPAM Based Microgels with CoFe2O4 Nanoparticles and Their Magnetic Response in Bulk and at Surfaces

The journal of physical chemistry. B, Jan 10, 2015

The present paper addresses the loading of thermoresponsive poly-N-isopropylacrylamide (PNIPAM) b... more The present paper addresses the loading of thermoresponsive poly-N-isopropylacrylamide (PNIPAM) based microgel particles with magnetic nanoparticles (MNP: CoFe2O4@PAA (PAA = poly(acrylic acid))) and their response to an external magnetic field. The MNP uptake is analyzed by transmission electron microscopy (TEM). Obviously, the charge combination of MNP and microgels plays an important role for the MNP uptake, but it does not explain the whole uptake process. The MNP uptake results in changes of size and electrophoretic mobility, which is investigated by dynamic light scattering (DLS) and a Zetasizer. The microgels loaded with MNP preserve their thermosensitivity, and they show magnetic separability and are considered as magnetic microgels. After adsorption at a surface the magnetic microgels are studied with a scanning force microscope and indentation experiments. The magnetic microgels show an elongation along the magnetic field parallel to the surface while the height of the micr...

Research paper thumbnail of A Magnetoresponsive Drug Delivery System via -Cyclodextrin Functionalized Magnetic Polymer Brushes

IEEE Transactions on Magnetics

Research paper thumbnail of Bio-inspired self-healing materials

Research paper thumbnail of We welcome our new editor-in-chief

Colloid and Polymer Science, 2015

Research paper thumbnail of Relationship between the network dynamics, supramolecular relaxation time and healing kinetics of cobalt poly(butyl acrylate) ionomers

Research paper thumbnail of Controlling the self-assembly of magnetic nanoparticles by competing dipolar and isotropic particle interactions

Journal of Colloid and Interface Science, 2014

Research paper thumbnail of Self-Healing Ionomers

From Principles to Applications, 2013

Research paper thumbnail of Magnetic Properties and Dielectrical Relaxation Dynamics in CoFe 2 O 4 @PU Nanocomposites

The Journal of Physical Chemistry C, 2011

Research paper thumbnail of One-step synthesis of functional Co nanoparticles for surface-initiated polymerization

Research paper thumbnail of Kinetic studies of surface-initiated atom transfer radical polymerization in the synthesis of magnetic fluids

Journal of Polymer Science Part A: Polymer Chemistry, 2009

Research paper thumbnail of A Magnetoresponsive Drug Delivery System via <formula formulatype="inline"><tex Notation="TeX">$\beta$</tex> </formula>-Cyclodextrin Functionalized Magnetic Polymer Brushes

IEEE Transactions on Magnetics, 2000