Formation of polymer blend microcapsules with distinct morphologies via phase separation: Effects of inter-polymer and polymer-nonsolvent incompatibilities
Journal
Journal of Molecular Liquids
Journal Volume
432
Start Page
127867
ISSN
0167-7322
Date Issued
2025-08-15
Author(s)
Abstract
Solidifying binary polymer solution droplets in a nonsolvent bath can form microcarriers with distinct morphologies. Dissipative particle dynamics simulations are used to explore the diverse final morphologies of the precipitate containing two immiscible polymers. The structure of the polymer blend precipitate depends on the inter-polymer incompatibility (χ12), the mole fraction of the two polymers (ϕ1,0), and the polymer-nonsolvent incompatibility (χ2N). Capsules with multi-compartment shells form when the inter-polymer incompatibility is lower than the polymer-nonsolvent incompatibility (χ12 < χ2N), while Janus particles develop when inter-polymer incompatibility is higher (χ12 > χ2N). Furthermore, altering the polymer-nonsolvent incompatibility from χ2N = χ1N to χ2N > χ1N leads to a morphology change in the shell of the microcapsule from multi-compartment to bilayer. For the bilayered microcapsule, the polymer with higher polymer-nonsolvent incompatibility (χ2N) prefers staying in the inner layer and solidifies earlier due to rapid oversaturation. Our results provide valuable insight into the formation of polymer blend microcapsule and the factors resulting in distinct morphologies.
Subjects
Bilayered structure
Janus particles
Microcapsule
Nonsolvent-induced phase separation
Polymer blend
Publisher
Elsevier BV
Type
journal article