Multicompartment polymeric colloids from functional precursor Microgel: Synthesis in continuous process

Raspberry-like poly(oligoethylene methacrylate-b-N-vinylcaprolactam)/polystyrene (POEGMA-b-PVCL/ PS) patchy particles (PPs) and complex colloidal particle clusters (CCPCs) were fabricated in two-, and one-step (cascade) flow process. Surfactant-free, photo-initiated reversible addition-fragmentation trans-fer (RAFT) precipitation polymerization (Photo-RPP) was used to develop internally cross-linked POEGMA-b-PVCL microgels with narrow size distribution. Resulting microgel particles were then used to stabilize styrene seed droplets in water, producing raspberry-like PPs. In the cascade process, different hydrophobicity between microgel and PS induced the self-assembly of the first formed raspberry parti-cles that then polymerized continuously in a Pickering emulsion to form the CCPCs. The internal structure as well as the surface morphology of PPs and CCPCs were studied as a function of polymerization condi-tions such as flow rate/retention time (Rt), temperature and the amount of used cross-linker. By perform-ing Photo-RPP in tubular flow reactor we were able to gained advantages over heat dissipation and homogeneous light distribution in relation to thermally-, and photo-initiated bulk polymerizations. Tubular reactor also enabled detailed studies over morphological evolution of formed particles as a func-tion of flow rate/Rt.(c) 2022 Elsevier Inc. All rights reserved.