One-pot synthesis of micron-sized polybetaine particles: innovative use of supercritical carbon dioxide

Bassett, Simon P.; Birkin, Natasha A.; Jennings, James; Champman, Emma; O'Reilly, Rachel K.; Howdle, Steven M.; Willcock, Helen

Abstract

Polybetaines exhibit unique properties combining anti-polyelectrolyte and low protein fouling behaviour, as well as biocompatibility. To date, the synthesis of polybetaine particles >50 nm has 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 3.0 × 10−2 mol L−1 and 1.8 × 10−1 mol L−1 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 was observed by SEM analysis for the optimised particles. The particles were readily re-dispersed in aqueous solution and light scattering measurements confirmed their low size dispersity.

Citation

Bassett, S. P., Birkin, N. A., Jennings, J., Champman, E., O'Reilly, R. K., Howdle, S. M., & Willcock, H. (in press). One-pot synthesis of micron-sized polybetaine particles: innovative use of supercritical carbon dioxide. Polymer Chemistry, 8, https://doi.org/10.1039/C7PY00455A

• Journal Article Type: Article
• Acceptance Date: Jul 2, 2017
• Online Publication Date: Jul 3, 2017
• Deposit Date: Oct 13, 2017
• Publicly Available Date: Oct 13, 2017
• Journal: Polymer Chemistry
• Print ISSN: 1759-9954
• Electronic ISSN: 1759-9962
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 8
• DOI: https://doi.org/10.1039/C7PY00455A
• Public URL: https://nottingham-repository.worktribe.com/output/870882
• Publisher URL: http://pubs.rsc.org/en/content/articlehtml/2017/py/c7py00455a
• Contract Date: Oct 13, 2017