Monitoring reactive microencapsulation dynamics using microfluidics

Igmar Polenz (1) , Quentin Brosseau (1) , Jean-Christophe Baret (2)

1 MPIDS - Max Planck Institute for Dynamics and Self-Organization
2 CRPP - Centre de recherches Paul Pascal

We use microfluidic polydimethylsiloxane (PDMS) devices to measure the kinetics of reactive encapsulations occurring at the interface of emulsion droplets. The formation of the polymeric shell is inferred from the droplet deformability measured in a series of expansion–constriction chambers along the microfluidic chip. With this tool we quantify the kinetic processes governing the encapsulation at the very early stage of shell formation with a time resolution of the order of the millisecond for overall reactions occurring in less than 0.5 s. We perform a comparison of monomer reactivities used for the encapsulation. We study the formation of polyurea microcapsules (PUMCs); the shell formation proceeds at the water–oil interface by an immediate reaction of amines dissolved in the aqueous phase and isocyanates dissolved in the oil phase. We observe that both monomers contribute differently to the encapsulation kinetics...

Mots clés: Microencapsulation; Microfluidic

Domaines: Matière Condensée [cond-mat]; Dynamique des Fluides [physics.flu-dyn]

Igmar Polenz, Quentin Brosseau, Jean-Christophe Baret. Monitoring reactive microencapsulation dynamics using microfluidics. Soft Matter, 2015, 11, ⟨10.1039/c5sm00218d⟩. ⟨hal-01122766⟩