Nanostrukturierte intelligente Polymermaterialien mit anpassungsfähigen Hafteigenschaften
Zusammenfassung der Projektergebnisse
In summary, we successfully developed and applied synthetic routes for the robust synthesis of switchable responsive and adaptive bicomponent polymer brushes with different architectures (linear, random and block copolymer ones) on flat and rough substrates and got an insight in their switchable and adaptable adhesion performance. Moreover, completely new systems based on non-homogeneous core-shell Janus particles were developed, which open new horizons in design of smart materials with advanced responsive and adaptive properties. The switchable and adaptive systems with different architectures, chemical and topographical design were systematically synthesized using surface initiated ATRP and thoroughly characterized and controlled with spectroscopic and null-ellipsometry, electrokinetic, contact angle, SEM, TEM, cryo-TEM, AFM- topography and AFM-force measurements using colloid probe-technique as well probe tack adhesion testing (in collaboration with Laboratory PPMD – ESPCI, Paris, France, Group of Prof. C. Creton). The following important surface and bulk properties of Polymer brush grafted layer: the length of grafted polymer chain; grafting density; composition of grafted polymers; glass transition temperature Tg of polymers; surface roughness; applied adhesives: surface chemical composition - hydrophilic, hydrophobic; rheological/mechanical properties - stiff/soft; adhesion parameters: control the normal preload; speed of debonding; contact time were systematically varied and investigated in order to control switchable and / adaptable adhesion performance. It was demonstrated that the same bicomponent polymer brush composed of an apolar and polar component can be reversibly switched between two states and adapted (for adaptable systems with low Tg and high mobility of polymer chains) where it is non-adhesive or extremely adhesive against a hydrophobic or hydrophilic soft or hard adhesive depending on environmental conditions, chemical composition, roughness, mechanical properties of adhesives and adhesion conditions. Furthermore, the extent of the reversible change in tack and colloid probe force measurements of different adhesives can be adjusted by the ratio between the two grafted polymers of the bicomponent brush layer. The technologically simple synthetic method introduces an ideal scenario for producing a new generation of materials with adaptive surfaces where the change in adhesion could now be induced by the adhesive itself depending on its surface energy and chemical composition. Such a strategy is especially promising in the medical and pharmaceutical fields as well as in cosmetic and food industry. In those fields, strategies to control adhesion reversibly and efficiently would be clearly useful and currently do not exist to the best of our knowledge. Finally, the experience and fundamental knowledge, obtained in the project period, on the preparation of smart polymeric materials and their responsive/adaptive adhesion performance will be further extended to the concept of design smart functional materials with advanced architectures and controllable interfacial/surface properties as well as understanding interactions between their single building blocks.
Projektbezogene Publikationen (Auswahl)
- Stimuli-Responsive Bicomponent Polymer Janus Particles by "Grafting from"/"Grafting to" Approaches, Macromolecules 2008, 41, (24), 9669-9676
Berger, S.; Synytska, A.; Ionov, L.; Eichhorn, K. J.; Stamm, M.
- The forces of interaction between poly(2-vinylpyridine) brushes as measured by optical tweezers, Macromolecules 2009, 42, (22), 9096-9102
Elmahdy, M. M.; Synytska, A.; Drechsler, A.; Gutsche, C.; Uhlmann, P.; Stamm, M.; Kremer, F.
- Biocompatible polymeric materials with switchable adhesion properties, Soft Matter 2010, 6, (23), 5907-5914
Synytska, A.; Svetushkina, E.; Puretskiy, N.; Stoychev, G.; Berger, S.; Ionov, L.; Bellmann, C.; Eichhorn, K.-J.; Stamm, M.
- Interaction forces between colloidal silica particles and annealed polyelectrolyte brushes at varying pH and salt concentration, Langmuir 2010, 26, (9), 6400-6410
Drechsler, A.; Synytska, A.; Uhlmann, P.; Elmahdy, M. M.; Stamm, M.; Kremer, F.
- A Comparative Study on Switchable Adhesion Between Thermoresponsive Polymer Brushes on Flat and Rough Surfaces, Soft Matter 2011, 7, 5691– 5696
Svetushkina, E.; Ionov, L.; Puretskiy, N.; Stamm, M.; Synytska, A.
- Engineering of Ultrahydrophobic Functional Coatings Using Controlled Aggregation of Bicomponent Core-Shell Janus Particles, Advanced Functional Materials 2011, 21 (12), 2338–2344
Berger, S.; Ionov, L.; Synytska, A.