Jump to main content
Jump to site search


Hydrocarbon based stabilisers for the synthesis of cross-linked poly(2-hydroxyethyl methacrylate) particles in supercritical carbon dioxide

Author affiliations

Abstract

An environmentally-friendly process to prepare well-defined cross-linked particles of poly(2-hydroxyethyl methacrylate) (PHEMA) was investigated. The dispersion polymerisation of 2-hydroxyethyl methacrylate (HEMA) with a cross-linker ethylene glycol dimethacrylate (EGDMA) was performed in supercritical carbon dioxide (scCO2). Stabilisers based only on vinyl acetate (VAc) and vinyl pivalate (VPi) random copolymers P(VAc-stat-VPi) were employed thus avoiding the use of silicone or fluorine based stabilisers which are normally required in scCO2. The effect of molecular weight and composition of the P(VAc-stat-VPi) stabilisers on the size and shape of the produced microparticles was investigated. A copolymer stabiliser with 56 : 44 (VAc : VPi) molar composition (Mn = 12.8 kg mol−1) was found to be the most efficient, resulting in well-defined spherical cross-linked PHEMA particles with a diameter of 1.2 μm. This particular stabiliser was found to provide good steric stabilisation for a range of cross-linker ratios and the addition of a co-monomer such as N-vinylpyrrolidone (NVP) allowed tuning of the properties of the microparticulate products. Finally, the stabiliser plays a second very important role. Partial hydrolysis of the ester groups of the stabiliser located on the surface of the microparticles leads to a hydrophilic surface with alcohol moieties and hence facilitates dispersion of the microparticles into water leading to valuable microgels.

Graphical abstract: Hydrocarbon based stabilisers for the synthesis of cross-linked poly(2-hydroxyethyl methacrylate) particles in supercritical carbon dioxide

Back to tab navigation

Supplementary files

Publication details

The article was received on 06 Jul 2019, accepted on 02 Oct 2019 and first published on 07 Oct 2019


Article type: Paper
DOI: 10.1039/C9PY00998A
Polym. Chem., 2019, Advance Article

  •   Request permissions

    Hydrocarbon based stabilisers for the synthesis of cross-linked poly(2-hydroxyethyl methacrylate) particles in supercritical carbon dioxide

    R. Parilti, A. Castañon, M. Lansalot, F. D'Agosto, C. Jérôme and S. M. Howdle, Polym. Chem., 2019, Advance Article , DOI: 10.1039/C9PY00998A

Search articles by author

Spotlight

Advertisements