INVESTIGADORES
MARTINO Debora Marcela
congresos y reuniones científicas
Título:
Block-copolymer controlled radical polymerization of vinylbenzylthymine (VBT): An application for controlled drug delivery devices
Autor/es:
A. BARBARINI; D. M. MARTINO
Lugar:
Washington
Reunión:
Conferencia; 14th Annual Green Chemistry & Engineering Conference; 2010
Resumen:
We carried out a systematical experimental
investigation on the block copolymer controlled radical polymerization of
styrene (St) and vinylbenzyl thymine (VBT). Two radical capping mechanisms were
compared: nitroxide-mediated living free-radical polymerization (NMP) using
2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) derivatives as stable radical
deactivators; and transition metal mediated polymerization or atom transfer
radical polymerization (ATRP) using a copper bromide (CuBr) as catalyst.
Several syntheses of block copolymers varying the comonomer composition, the
nitroxide radical/catalyst concentrations and temperature were examined.
Samples were taken along the reactions to determine monomer conversion,
chemical composition, and molecular weight distribution. The radical nature and
concentrations were measured and analyzed with the aid of electron paramagnetic
resonance spectroscopy (EPR), providing important information on the
mechanisms. The experimental results provide complementary information on the
characteristics and properties of styrene based copolymers containing thymine,
that are crucial for developing new classes of environmentally benign,
non-toxic materials.