ABSTRACT
The diverse morphologies of aggregates formed by the self-assembly of block copolymers in selective solvents have attracted widespread attention, but the design of aggregate shapes is still limited owing to the thermodynamic favorability of sphere formation. In this paper, we report our discovery that polyhedral aggregates can be formed by the self-assembly of 1H,1H,2H,2H-perfluoro-1-dodecanol (PFD)-grafted amphiphilic polystyrene-b-poly(acrylic acid) (PS-b-PAA-g-PFD) copolymers in water at room temperature. It is determined that the crystallization of fluorocarbon side chains at the surface of PS-b-PAA-g-PFD aggregates induces the formation of a polyhedral shape. The morphology of aggregates can be controlled by the dialysis temperature, the grafting ratio of PFD in PS-b-PAA-g-PFD copolymers, and the initial copolymer concentration. The layers of polyhedral aggregates show excellent antibacterial adhesion properties. We anticipate that this method will expand the promise of self-assembly for the synthesis of a series of nonspherical micellar nanoparticles, which have promising applications in various fields.
Subject(s)
Acrylates/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Escherichia coli/drug effects , Micelles , Polymers/chemistry , Polystyrenes/chemistry , Staphylococcus aureus/drug effects , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Surface PropertiesABSTRACT
Recently, although several unconventional luminescent polymers have been synthesized, it still remains a significant challenge to prepare various new fluorescent polymers by functionalization of nonfluorescent polymers. A nonfluorescent 1 H,1 H,2 H,2 H-perfluoro-1-decanol grafted to nonfluorescent polystyrene- b-poly(acrylic acid) block copolymers through simply esterification reaction can exhibit strong blue emission. On the basis of control experiments and theoretical simulation, we have proposed that the luminescence stems from interchain n â π* interaction between the lone pair (n) of hydroxyl O atoms of carboxyl units and empty π* orbital of ester carbonyl unit. In addition, the fluorescent polymers are successfully employed for fluorescence imaging in living HeLa cell.
