Branched Polyphosphazenes with Controlled Dimensions
Sprache des Titels:
Englisch
Original Kurzfassung:
ABSTRACT: Using living cationic polymerization, a series of
polyphosphazenes is prepared with precisely controlled
molecular weights and narrow polydispersities. As well as
varying chain length through the use of a living polymerization,
amine-capped polyalkylene oxide (Jeffamine) side chains
with varied lengths are grafted to the polymer backbone to
give a series of polymers with varied dimensions. Dynamic
light scattering and size exclusion chromatography are used
to confirm the preparation of polymers with a variety of controlled
dimensions and thus hydrodynamic volumes. Furthermore,
it is demonstrated how the number of arms per repeat
unit, and thus the density of branching, can also be further
increased from two to four through using a one-pot thiolactone
conversion of the Jeffamines, followed by thiol-yne addition
to the polyphosphazene backbone. These densely
branched, molecular brush-type polymers on a biodegradable
polyphosphazene backbone all show excellent aqueous solubility
and have potential in drug-delivery applications. VC 2013
Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.
2013, 51, 4467?4473
Forschungs-