ja003304u_si_001.pdf (308.2 kB)
Encapsulation of Functional Moieties within Branched Star Polymers: Effect of Chain Length and Solvent on Site Isolation
journal contribution
posted on 2000-12-13, 00:00 authored by Stefan Hecht, Nikolay Vladimirov, Jean M. J. FréchetPorphyrin and pyrene photoactive cores have been encapsulated within an isolating polymeric shell
using an efficient and general strategy based on the use of dendritic initiators for the ring-opening polymerization
of ε-caprolactone to yield functional core star polymers. The isolation of the core functionalities has been
studied using fluorescence quenching and fluorescence resonance energy transfer (FRET) techniques as well
as solvatochromic probes. With increasing chain length as well as solvent polarity, enhanced site isolation of
the core has been observed. These findings have been correlated to actual molecular dimensions independently
measured by pulsed field gradient spin−echo (PGSE) NMR. The developed synthetic methodology offers a
rapid route to efficient encapsulation of functional moieties and therefore has potential for the design of new
materials.