Molecular dynamics of a biodegradable biomimetic ionomer studied by broadband dielectric spectroscopy.
Broadband dielectric spectroscopy was used to investigate the bulk molecular dynamics of a recently developed biodegradable biomimetic ionomer potentially useful for biomedical applications. Isothermal dielectric spectra were gathered for a phosphoryl choline (PC)-functionalized poly(trimethylene carbonate) (PTMC) ionomer and unfunctionalized PTMC at temperatures ranging from 2 to 60 degrees C over a broad frequency range of 10(-3) to 10(6) Hz. Four relaxations were clearly identified, two of which were shown to stem from the PTMC polymer backbone. A detailed analysis showed that the formation of zwitterionic aggregates was responsible for the material's bulk functionality and that bulk conduction processes may provide useful information for assessing the PC ionomer as a candidate for drug delivery applications. Finally, it was concluded that absorbed water concentrates around the aggregates, resulting in an increased mobility of the PC end-groups.
Welch
Ken
K
Department of Engineering Sciences, The Angström Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala, Sweden. ken.welch@angstrom.uu.se
Nederberg
Fredrik
F
Bowden
Tim
T
Hilborn
Jöns
J
Strømme
Maria
M
D018716:Molecular Mimicry; D015335:Molecular Probes; D013057:Spectrum Analysis / Q000379:methods*; D013696:Temperature
D015335:Molecular Probes