Reverse Block Sequence in Self-Immolative Poly(benzyl ether)-Based Amphiphiles for Tailoring End Groups and Self-Assembly Behavior.

This paper reports a modular design of self-immolative poly(benzyl ether) (PBE) amphiphiles that allows precise control over polymer chain structure, end-group placement, and degradation behavior. By tuning block sequences and exposing reactive end groups, these amphiphiles undergo efficient head-to-tail depolymerization upon external stimuli. Structural variations in the monomers enable micelle formation with end groups displayed on the surface, while the carboxylate content in the hydrophilic block influences global micelle morphology. The resulting micelles are degradable in aqueous environments and can transform into spherical structures when combined with conventional surfactants. As a proof of concept, small-molecule cargos were successfully loaded and released from the mixed micelles on demand. This design platform offers a versatile route to create functional, stimulus-responsive surfactants with tunable assembly, degradation, and controlled release capabilities.