Synthesis of Crosslinkable Micelles from DiblockAmphiphilic Copolymers Based on Vinylbenzyl Thymine and VinylbenzylTriethylammonium Chloride

A. BARBARINI; D. A. ESTENOZ; D. M. MARTINO

JOURNAL OF APPLIED POLYMER SCIENCE

JOHN WILEY & SONS INC

Lugar: New York; Año: 2015 vol. 132 p. 6146 - 6156

0021-8995

Polymeric micelles (PMs) composed of self-assembledamphiphilic block copolymers were synthesized from vinylbenzyl thymine (VBT)and vinylbenzyl triethylammonium chloride (VBA) exhibiting improved physicalstability. Three diblock copolymers of different chemical compositions andsimilar molecular weights (polydispersities below 1.5) were obtained viaNitroxide Mediated Radical Polymerization. Critical Micelle Concentration (CMC)was determined by dye micellization method, the shift of the absorption peak ofthe anionic Eosin Y (EY) due to the interactions with non-assembled chains andauto-assembled copolymers was followed. Polymeric systems exhibited goodstability revealing that a higher proportion of cationic monomers in thediblock reduces the CMC. Furthermore, after the core of PMs wasphotocrosslinked by UV irradiation, the CMC decreases notably. Kinetic releasestudies using EY dye as probe demonstrated that both, higher VBA ratios in thepolymer and higher UV-irradiation, slow down the dye release.