Multicompartment Micelles from pH-Responsive Miktoarm Star Block Terpolymers

Abstract

We describe the synthesis of pH-responsive miktoarm star block terpolymers mu-[polystyrene][poly(ethylene oxide)][poly(2-(dimethylamino)ethyl acrylate)] (mu-SODA) using a combination of two successive living anionic polymerizations and one reversible addition-fragmentation chain-transfer polymerization. Poly[2-(dimethylamino)ethyl acrylate] (PDMAEA) is a weak polybase that is hydrophilic at low pH and hydrophobic at high pH because of the protonation of the dimethylamino functional group with decreasing pH. In addition, our results suggest that PDMAEA is immiscible with polystyrene (PS), a feature that is desirable for the formation of multicompartment micelles. Using a combination of dynamic light scattering and cryogenic transmission electron microscopy, we demonstrate that mu-SODA micelles formed in water evolve from mixed corona (PEO + PDMAEA corona; PS core) and predominantly spherical micelles to multicompartment (PEO corona; PS + PDMAEA core) micelles with increasing pH.

Responsive Vesicles from the Self‐Assembly of Crystalline‐Coil Polyferrocenylsilane‐block‐Poly(ethylene Oxide) Star‐Block Copolymers

“…Very recently, the synthesis of dendritic stars with blocks of polyglycidol and poly (tert-butyl glycidyl ether) has been demonstrated. [30] Synthetically most often more demanding than block structures, the preparation and aggregation of responsive star-shaped m- [31] and hetero-arm [32] structures have also been pursued.…”

Water-Soluble Stimuli Responsive Star-Shaped Segmented Macromolecules

“…Different pH responsiveness of self-assemblies in aqueous media of two miktoarm star terpolymers, bearing similar in nature arms with the previous one, i.e., hydrophobic PS, hydrophilic PEO and pH-sensitive PDMAEMA arms, was observed [56]. At low pH, the stars formed spherical micelles with PS cores and mixed hydrophilic PEO and positively charged PDMAEMA arms in the coronas.…”

Temperature‐Sensitive (BA)(AC)2 Miktoarm Star Diblock Copolymer Based on PMMA, PPEGMA, and PNIPAm

“…[1][2][3][4][5][6][7] Compared with their linear counterparts, star polymers exhibit unique morphologies, properties, and functions, [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] especially miktoarm star polymers. [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] This is because a miktoarm star polymer combines different polymer arms into a molecule through a single core. For example, Liu et al [ 15 ] synthesized the ABC miktoarm polymer poly(ethylene oxide)-poly(2-(diethylamino)ethyl methacrylate)-poly(methacrylic acid) (PEG-PDEA-PMAA).…”