Seminario «Tuning microgel internal structure and mechanical properties by copolymerization, to control responsiveness, interactions and rheology», impartido por Marco Laurati (Department of Chemistry «Ugo Schiff», University of Florence).
Resumen:
Microgels are micron-sized crosslinked polymer networks that can respond to stimuli such as temperature or pH, finding application in drug delivery, water harvesting, cell culture, selective filtration, art conservation, among others. For exploiting their full potential in these applications, precise control over their stimulus response, interactions and rheology is highly desirable. This can be achieved through the design of the internal structure of the polymer network and the single particle mechanical properties. I will present in this talk one example of this kind of design based on the use of copolymerization of N-isopropylacrylamide (NIPAM) with oligo (ethylene glycol) methyl ether methacrylate (OEGMA) monomers of different length. Depending on the OEGMA length, the microgels present a different internal architecture, as determined by small angle scattering experiments, changing from a star-like density profile to a more compact but still heterogeneous density profile. The comonomer distribution is also different within these structures, as assessed by comparison with monomer-resolved simulations, and influences the bulk modulus and the interactions of the microgels, therefore influencing the phase behavior of the system. Furthermore, the internal architecture and single particle mechanics are key elements in the rheological behavior of dense microgel suspensions, in particular regarding yielding, flow, and the onset of shear banding. The proposed approach can be extended to mixtures of thermoresponsive polymers, including fully biocompatible systems.
- Fecha: Jueves, 27 de marzo de 2025
- Lugar: Facultad de Ciencias – Aula A15
- Horario: de 13:00 a 14:00
- Organiza: Grupo de Física de Fluidos y Biocoloides
- Más información: http://biocol.ugr.es