Layer-by-layer adsorption of polyelectrolytes on microgels as soft and porous colloidal substrate

• Applicant: Professor Dr. Walter Richtering
• Subject Area: Experimental and Theoretical Physics of Polymers
• Term: from 2006 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 26702835

This proposal investigates the layer-by-layer assembly of polyelectrolyte multilayers on unconventional soft and porous supports as provided by microgels. Microgels, such as Poly(N-isopropylacrylamide) (PNIPAM), are thermosensitive materials and undergo a volume phase transition temperature at 32°C. This makes them potential candidates for use in drug encapsulation, transport, and controlled release in the body. We synthesise different core-shell systems based on PNIPAM to constitute building blocks of various mesh size. The challenge is to use layer-by-layer deposition of polyelectrolyte multilayers on a substrate of changing size with temperature, whereby the polyelectrolytes can also penetrate the soft and porous substrate to confer novel properties via surface modification. We shall investigate parameters influencing the formation and growth behaviour (molecular weight, charge density, salt, ionic strength, pH, temperature) and characterise both the substrates and the multilayers using various techniques. The project aims at a better understanding of the interactions and the physico-chemical aspects coming into play not only within the multilayers as build on soft and porous substrates but also between the layer and the thermosensitive substrate.

• DFG Programme: Research Grants
• Participating Person: Dr. John Erik Wong