First-time application of a combination of electrospray ionisation (ESI) polymer-deposition and dielectric barrier discharge for an improved adhesion between carbon fibres and polyurethane

• Applicant: Dr. Sascha Wettmarshausen
• Subject Area: Polymer Materials ; Chemical and Thermal Process Engineering
• Term: from 2010 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 191070037

The scholarship aims at developing a new application of electrospray ionisation, which has found widespread use in mass spectroscopy, in the deposition of ultra-thin polymer layers. This new polymer film deposition technique allows depositing extremely thin adhesion-promoting interlayers that are expected to improve the adhesion between carbon fibres and polyurethane (PU) elastomers. It is planned to use electrospray ionisation-based (ESI) polymer deposition in combination with carbon fibre surface activation in the afterglow of a dielectric barrier discharge. This new approach has been exemplary applied to polymer surfaces. Due to the electrophoretic character of the ESI process and the electrical conductivity of carbon fibres, it is expected that ESI allows to establish pin-hole free deposition of ultra-thin adhesion-promoting polymer layers on carbon fibres. A main advantage of the proposed method compared to plasma-based coating processes is the fragmentation-free deposition of individualized polymer molecules. ESI-based polymer deposition on carbon fibres that were cleaned and activated in the afterglow of a dielectric barrier discharge plasma in air, argon, or oxygen is expected to result in a strongly adherent, very thin polymer, acting as adhesion promoter to polyurethane matrices. The polymer solution deposited by ESI, will be chosen to contain polymers of monosort functionalities. These groups can form chemical urethane or urea bonds to isocyanate endgroups of PU prepolymers. As a result, strongly enhanced adhesion between carbon fibres and polyurethane matrices is expected. Using this innovative application of the newly-developed ESI film deposition process it should be possible to generate specifically-tailored and optimized interface layers on carbon fibres under consideration of low-cost atmospheric plasma and deposition processes.XPS, FTIR and REM as well as measurement of zeta-potential and mechanical adhesion will be used for characterization.

• DFG Programme: Research Fellowships
• International Connection: United Kingdom
• Host: Professor Dr. Alexander Bismarck