文摘
Shape amphiphiles with distinct shapes and amphiphilic properties can be used as fundamental building blocks in the fabrication of novel structures and advanced materials. In this research synthesis and self-assembly of monotethered single-chain nanoparticle shape amphiphiles are reported. Poly(2-(dimethylamino)ethyl methacrylate)-block-polystyrene (PDMAEMA-b-PS) was synthesized by two-step reversible addition鈥揻ragmentation chain transfer (RAFT) polymerization. The PDMAEMA blocks were intramolecularly cross-linked by 1,4-diiodobutane (DIB) at significantly low concentrations, and PS-tethered PDMAEMA single-chain nanoparticles were prepared. Gel permeation chromatograph, 1H NMR and transmission electron microscopy results all indicated successful synthesis of the structures. The controlled self-assembly of the shape amphiphiles in selective solvents was investigated. Depending on the size of the single-chain nanoparticles, the shape amphiphiles self-assemble into strawberry-like micelles, a structure with single-chain nanoparticles in the corona and PS in the core, or vesicles in aqueous solutions. Similar to the self-assembled structures in aqueous solution, the morphology of the aggregates in methanol changes from micellar structure to vesicular structure with the decrease of the PDMAEMA single-chain nanoparticles size. In cyclohexane, the shape amphiphiles self-assemble into bunchy micelles with single-chain nanoparticles in the cores and linear PS in the coronae.