H Willcock Polymer Chemistry scCO2 2017.pdf (2.36 MB)
One-pot synthesis of micron-sized polybetaine particles; innovative use of supercritical carbon dioxide
journal contribution
posted on 2017-07-27, 12:15 authored by Simon P. Bassett, Natasha A. Birkin, James Jennings, Emma Chapman, Rachel K. O'Reilly, Steven M. Howdle, Helen WillcockHelen WillcockPolybetaines exhibit unique properties including anti-polyelectrolyte and low protein fouling behaviour, as well as biocompatibility. We recently presented the synthesis of ca. 20 nm polybetaine particles by aqueous RAFT polymerisation, but the synthesis of larger particles proved to be extremely challenging with standard emulsion and dispersion techniques being unsuccessful. Here we present the first reported synthesis of micron-sized, discrete cross-linked polybetaine
particles, using polymerisation in scCO2 with methanol as a co-solvent. Discrete particles are produced only when the methanol is efficiently removed in-situ using scCO2 extraction. A relatively high crosslinking agent initial concentration (10 wt%) was found to result in the most well defined particles, and particle integrity reduced as the crosslinking agent initial concentration was decreased. A monomer loading of between 3.0x10-2 mol/L and 1.8x10-1 mol/L resulted in discrete
micron sized particles, with significant agglomoration occuring as the monomer loading was increased further. A spherical
morphology and extremely low size dispersity is observed by SEM analysis for the optimised particles. The particles are readily re-dispersed in aqueous solution and light scattering measurements confirm their low size dispersity.
History
School
- Aeronautical, Automotive, Chemical and Materials Engineering
Department
- Materials
Published in
Polymer ChemistryVolume
8Issue
31Pages
4557 - 4564Citation
BASSETT, S.P. ...et al., 2017. One-pot synthesis of micron-sized polybetaine particles; innovative use of supercritical carbon dioxide. Polymer Chemistry, 8 (31), pp. 4557-4564.Publisher
© The Royal Society of ChemistryVersion
- AM (Accepted Manuscript)
Publisher statement
This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/Acceptance date
2017-07-02Publication date
2017-07-03Notes
This paper was published in the journal Polymer Chemistry and the definitive published version is available at http://dx.doi.org/10.1039/C7PY00455A.ISSN
1759-9954eISSN
1759-9962Publisher version
Language
- en