Filtern
Erscheinungsjahr
Dokumenttyp
- Vortrag (47) (entfernen)
Sprache
- Englisch (47) (entfernen)
Referierte Publikation
- nein (47)
Schlagworte
- Acrylamide (5)
- Thermoresponsive polymers (5)
- Diaminopyridine (4)
- Thermoresponsive polymer (4)
- UCST-type polymer (4)
- Vesicles (4)
- H bonds (3)
- Janus dendrimers (3)
- UCST-type polymers (3)
- 2,6-diaminopyridine (2)
Organisationseinheit der BAM
- 6 Materialchemie (8)
- 6.0 Abteilungsleitung und andere (8)
- 5 Werkstofftechnik (5)
- 5.3 Polymere Verbundwerkstoffe (5)
- 5.4 Multimateriale Fertigungsprozesse (2)
- 4 Material und Umwelt (1)
- 4.4 Thermochemische Reststoffbehandlung und Wertstoffrückgewinnung (1)
- 8 Zerstörungsfreie Prüfung (1)
- 8.6 Faseroptische Sensorik (1)
Eingeladener Vortrag
- nein (47)
The demand for high-performance materials has strongly increased over the last decade. One way to improve their performance is to introduce material gradients as found in Nature (for example squid beaks, spider fangs, mussel byssal threads).
One path towards the achievement of such material gradients is the synthesis of hybrid (gradient) copolymers, for instance based on silane and organic monomers. Since not all gradient copolymers can be synthesized by utilising the reactivity ratios of the monomers, forced gradients have to be used. However, in order to obtain gradient copolymers at high conversions, living or pseudo-living copolymerizations have to be performed and so far only few hybrid (organic / inorganic) gradient copolymers have been reported. In this contribution we will present the synthesis of a novel organic / inorganic hybrid copolymer via controlled radical polymerization.
One of the holy grails in chemistry is to reconstruct some of life’s functions with synthetic materials. In this contribution, we demonstrate that “simple” macromolecular architectures such as dendritic amphiphiles, Janus dendrimers, thermoresponsive and hybrid organic-inorganic (co)polymers enable to mimic some of the functions of proteins for biomineralization, natural bactericides, biological membranes or the stimuli-responsive cytoskeleton.
One of the holy grails in chemistry is to reconstitute some of life’s functions with or within synthetic materials. In this contribution, we demonstrate that “simple” macromolecular architectures such as dendritic amphiphiles, Janus dendrimers, thermoresponsive and hybrid organic-inorganic (co)polymers enable to mimic some of the functions of proteins for biomineralization, natural bactericides, biological membranes or the stimuli-responsive cytoskeleton.
Lightweighting as a cross-cutting technology contributes significantly to achieve the European Green Deal goals. Based on, but not limited to, advanced materials and production technologies, the demand for natural resources and CO2 emmissions are reduced by lightweighting during production, as well as use phase. Therefore, lightweighting is a crucial transformation technology assisting in decoupling economic growth from resource consumption. In this manner, lightweighting contributes significantly as a key technology of relevance for many industrial sectors such as energy, mobility, and infrastructure, towards resource efficiency, climate action and economic strength, as well as a resilient Europe. To strengthen international partnerships, addressing global issues of today at the edge of science with high performance lightweight material based on carbon fibers, an overview about the BAM expertise in carbon fiber reinforced materials is given.
Unilamellar vesicles self-assembled in water from natural and synthetic phospholipids (liposomes), amphiphilic block copolymers (polymersomes), and more recently amphiphilic Janus dendrimers (dendrimersomes) as hollow soft structures in the nano size regime have attracted increasing interest as they can mimic primitive and contemporary biological membranes, and can be configured into biomimetic nanocapsules with application in nanomedicine such as gene, proteins and drug carriers or theranostics. Compared to other amphiphilic structures, the molecular structure of Janus dendrimers can be precisely controlled: by using the vast range of tools from organic chemistry their size, architecture, density, generation as well as the number of endgroups of the individual dendrons can be modified as desired. Unfortunately, the controlled production of the supramolecular aggregates made thereof is still a challenging task. Conventional batch-based techniques such as the solvent injection method or the film hydration method typically go along with a lack of control over mixing and thus over size, morphology and size distribution. The micromixer technology is a promising method for the controlled preparation of supramolecular assemblies as it allows control of mixing at microscale level. In addition, such microfluidic systems benefit from a high mixing efficiency, a low mixing time as well as from a reproducible and continuous synthesis.
Herein, we report on the microfluidic-controlled self-assembly of Janus dendrimers as dendrimersomes and the impact of the mixing parameters on the self-assembly process.
Vesicles self-assembled in water from natural and synthetic phospholipids (liposomes), amphiphilic block copolymers (polymersomes), and more recently amphiphilic Janus dendrimers (dendrimersomes) -5 as hollow soft structures in the nano size regime have attracted increasing interest as they can mimic primitive and contemporary biological membranes, and can be configured into biomimetic nanocapsules with application in nanomedicine such as gene, proteins and drug carriers or theranostics.
Compared to other amphiphilic structures, the molecular structure of Janus dendrimers can be precisely controlled: by using the vast range of tools from organic chemistry their size, architecture, density, generation as well as the number of end groups of the individual dendrons can be modified as desired.
Unfortunately, the controlled production of the supramolecular aggregates made thereof is still a challenging task. Conventional batch-based techniques such as the solvent injection method or the film hydration method typically go along with a lack of control over mixing and thus over size, morphology and size distribution. The micromixer technology is a promising method for the controlled preparation of supramolecular assemblies as it allows control of mixing at microscale level. In addition, such microfluidic systems benefit from a high mixing efficiency, a low mixing time as well as from a reproducible and continuous synthesis.
Herein, we report on the microfluidic-controlled self-assembly of Janus dendrimers as dendrimersomes and the impact of the mixing parameters on the self-assembly process.
Vesicles self-assembled in water from natural and synthetic phospholipids (liposomes), amphiphilic block copolymers (polymersomes), and more recently amphiphilic Janus dendrimers (dendrimersomes) -5 as hollow soft structures in the nano size regime have attracted increasing interest as they can mimic primitive and contemporary biological membranes, and can be configured into biomimetic nanocapsules with application in nanomedicine such as gene, proteins and drug carriers or theranostics.
Compared to other amphiphilic structures, the molecular structure of Janus dendrimers can be precisely controlled: by using the vast range of tools from organic chemistry their size, architecture, density, generation as well as the number of end groups of the individual dendrons can be modified as desired.
Unfortunately, the controlled production of supramolecular aggregates made thereof is still a challenging task. Conventional batch-based techniques such as the solvent injection method or the film hydration method typically go along with a lack of control over self assembly/mixing and thus over size, morphology and size distribution of the vesicles.
The micromixer technology is a promising method for the controlled preparation of supramolecular assemblies as it allows control of mixing at microscale level. In addition, such microfluidic systems benefit from a high mixing efficiency, a low mixing time as well as from a reproducible and continuous production of soft nanoparticles. Herein, we report on the microfluidic-controlled self-assembly of Janus dendrimers as dendrimersomes and the impact of the mixing parameters on the self-assembly process.
Vesicles self-assembled in water from natural and synthetic phospholipids (liposomes), amphiphilic block copolymers (polymersomes), and more recently amphiphilic Janus dendrimers (dendrimersomes) as hollow soft structures in the nano size regime have attracted increasing interest as they can mimic primitive and contemporary biological membranes, and can be configured into biomimetic nanocapsules with application in nanomedicine such as gene, proteins and drug carriers or theranostics.
Compared to other amphiphilic structures, the molecular structure of Janus dendrimers can be precisely controlled: by using the vast range of tools from organic chemistry their size, architecture, density, generation as well as the number of end groups of the individual dendrons can be modified as desired.
Unfortunately, the controlled production of the supramolecular aggregates made thereof is still a challenging task. Conventional batch-based techniques such as the solvent injection method or the film hydration method typically go along with a lack of control over mixing and thus over size, morphology and size distribution. The micromixer technology is a promising method for the controlled preparation of supramolecular assemblies as it allows control of mixing at microscale level. In addition, such microfluidic systems benefit from a high mixing efficiency, a low mixing time as well as from a reproducible and continuous synthesis.
Herein, we report on the microfluidic-controlled self-assembly of Janus dendrimers as dendrimersomes and the impact of the mixing parameters on the self-assembly process.
This presentation is a summary of the work from the past 20 years’ development of PMC-testing at the BAM-FB 5.3 with respect to safety-relevant design of advanced light weight structures in aircraft, wind turbine and automotive applications. The talk begins with wood as an example from nature, and emphasizes that load case, fiber architectural design and the production process and quality have to go hand in hand to generate an advanced light weight structure. Since PMC-relevant basic findings of mankind span across hundreds of years, high-performance composite applications today are based more on long term experiences than on breakthrough inventions of modern days.
In the second part of the talk, future plans and projects of FB-5.3 are presented, specifically addressing H2-safety, circular economy, recycling by design and digitalization of PMC-technologies.
At high temperatures and in harsh environments ceramic springs are often superior to metallic springs and allow for innovative solutions. A recently proposed application involves ceramic springs with metallized surfaces as capacitive force sensor. A strictly linear stress-strain characteristic of the spring is a precondition for such a sensor.
Helical ceramic springs with rectangular cross-section have been produced from sintered hollow cylinders. Alumina, ATZ, Y-TZP, and Ce-TZP springs with identical dimensions were characterized and compared regarding deformation behavior.
Spring deformation was investigated under various load scenarios.
Dynamic compression was performed with deformation speeds from 0.3 to 30 mm/min. Spring constants of alumina springs are strain rate independent. By contrast, Y-TZP spring constant increases by approximately 3 % within the experimental framework.
A high-precision test facility was developed to characterize spring displacement in nm range under static tensile load over long periods of time. Spring elongation with asymptotic course was observed for zirconia containing materials at room temperature. This effect is particularly strong in the case of Y-TZP. Up to 0.3 % time-dependent elongation was measured after 24 h under constant load. Deformation is completely reversible after unloading. Alumina springs do not show any time-dependent deformation under identical test conditions.
Contrary to alumina springs, a non-linear stress-strain behavior of TZP springs at room temperature was proved in both test series. It is supposed, that pseudo-elasticity caused by stress-induced phase transformation from tetragonal to monoclinic is responsible for this special behavior of TZP springs.
One of the holy grails in chemistry is to reconstruct some of life’s functions within synthetic materials. In this contribution, we demonstrate that “simple” macromolecular architectures such as dendritic amphiphiles, Janus dendrimers, thermoresponsive and hybrid organic-inorganic (co)polymers enable to mimic some of the functions of proteins for biomineralization, natural bactericides, biological membranes or the stimuli-responsive cytoskeleton.