Investigation of the morphology of biodegradable soft colloids

The aim of this project is to study the morphology of biodegradable soft colloids (microgels) made of hydroxypropyl cellulose (HPC). Stimuli-responsive microgels are of great interest for a variety of applications (functional coatings, viscosity modifiers, healthcare). For most processing needs (from injection to coatings), knowledge of the particle morphology is of utmost importance to tailor and predict the properties of dense suspensions and the interaction with interfaces. Un to now, the vast majority of fundamental and applied research focused on synthetic microgels. However, the growing interest in sustainability and biocompatibility calls for the development of novel “green” alternatives. We here focus on HPC, which allows synthesizing temperature-responsive particles that are biocompatible and biodegradable. To investigate their morphology, we plan to obtain form factors as a function of the synthesis protocols employed (reaction temperature and molecular weight), and compare them with monomer-resolved simulations from collaborators. We then plan to quantify the particle softness by using a recently introduced methodology to exert a controlled osmotic stress onto the microgels with partially deuterated linear polymers, using SANS with contrast variation to extrapolate the resulting microgels size. Overall, these results will be of fundamental importance in designing novel soft colloids that grant sustainable alternatives for the development of responsive materials.