Flexible nano coatings

We are investigating gas phase and surface processes relevant for plasma coating and etching processes. Thorough understanding of the energetic processes including simulations enables us to tailor functionalized surfaces considering the flexibility of substrates such as fibers, textiles, membranes etc.

Requirements for applications in aqueous environments are met by our high performing and permanent plasma coatings, also regarding the interaction of water with the surface and sub-surface (bioresponse, corrosion, wettability, adhesion, defined degradability etc.). As a research highlight, the orientation of water molecules within hydrophobic-to-hydrophilic layers induces additional interaction forces modulating, for example, protein adsorption.

Our knowledge extends to the successful transfer of plasma processes (etching, cleaning, plasma polymerization, sputtering) to industry supported by pilot-plant reactors both for web and fiber coating as well as simulation tools including production cost models.

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Reel-to-reel plasma process for fiber treatmentReel-to-reel plasma process for fiber treatment
Activities

- Deposition of plasma coatings with film properties such as hydrophilic/ hydrophobic, antimicrobial, antistatic, conductive,

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permanence and washing fastness, friction-reducing, phase-change etc. without influencing the substrate (e.g. textile) properties.

- Formation of vertical chemical gradient films through variation of plasma conditions during deposition reducing aging effects, improving adhesion, enabling well-controlled drug delivery and affecting protein adsorption.

- Etching processes on polymers exposing embedded structures to the surface or widening pores.

- Development and modification of plasma reactors supporting the optimization of plasma processes, also regarding scalability. By using pilot-plant reactors the conditions for the transfer of plasma processes into industry are examined.

- Simulation of gas flow within plasma reactors and transport of film-forming species to substrate surfaces supporting process optimization and up-scaling.

- Plasma processing of low vapor pressure liquids to obtain thin, freely floating films. Partly crosslinking of liquid molecules among each other and with the plasma-polymerized film leads to functional surfaces showing durable hydrophilic properties.

 

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Simulation of the convective gas flow and the diffusion of film forming species (2D) in a plasma reactor: The precursor gas is flowing from the inlet at the top to the outlet at the bottom. Film-forming species originate in the plasma area (indicated by the oval area with black border) above the substrate (white bar). The color plot shows the concentration of film-forming species. The streamlines indicate their transport through the reactor and to the substrate surface where they adsorb.