Controlling Kinetic Pathways in Demixing Microgel-Micelle Mixtures.

ABSTRACT: We investigate the temperature-dependent phase behavior of mixtures of poly(N-isopropylacrylamide) (pNIPAM) microgel colloids and a triblock copolymer (PEO-PPO-PEO) surfactant. Usually, gelation in these systems results from an increase in temperature. Here we investigate the role of the heating rate, and surprisingly, we find that this causes the mechanism of aggregation to change from one which is driven by depletion of the microgels by the micelles at low temperatures to the association of the two species at high temperatures. We thus reveal two competing mechanisms for attractions between the microgel particles which can be controlled by changing the heating rate. We use this heating-rate-dependent response of the system to access multiple structures for the same system c

SUBMITTER: Fussell SL 

PROVIDER: S-EPMC9878723 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature