Publications by authors named "Christian Steinmetz"

The phase behavior of block copolymers (BCPs) at the water-oil interface is influenced by the segmental interaction parameter ( ) and chain architecture. We synthesized a series of star block copolymers (s-BCPs) having polystyrene (PS) as core and poly(2-vinylpyridine) (P2VP) as corona. The interaction parameters of block-block ( ) and block-solvent ( ) were varied by adjusting the pH of the aqueous solution.

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To understand and resolve adsorption, reconfiguration, and equilibrium conformations of charged star copolymers, we carried out an integrated experimental and coarse-grained molecular dynamics simulation study of the assembly process at the oil-water interface. This is important to guide development of novel surfactants or amphiphiles for chemical transformations and separations. The star block copolymer consisted of arms that are comprised of hydrophilic-hydrophobic block copolymers that are covalently tethered the hydrophobic blocks to one point.

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Triple-stimuli-responsive PEG-based materials are prepared by living anionic ring-opening copolymerization of ethylene oxide and vinyl ferrocenyl glycidyl ether and subsequent thiol-ene postpolymerization modification with cysteamine. The hydrophilicity of these materials can be tuned by three stimuli: (i) temperature (depending on the comonomer ratio), (ii) oxidation state of iron centers in the ferrocene moieties, and (iii) pH-value (through amino groups), both in aqueous solution and at the interface after covalent attachment to a glass surface. In such materials, the cloud point temperatures are adjustable in solution by changing oxidation state and/or pH.

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The Bonebridge (®) (BB, Med-El) is a newly designed transcutaneous active bone conductive implant with functional outcome similar to percutaneous bone-anchored hearing systems (BAHS). It is currently approved only for patients ≥18 years. Since the BB allows the skin to remain intact and therefore should be able to overcome some of the issues related to percutaneous BAHS including skin reactions, wound infection and implant extrusion, it would be especially attractive for use in children.

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