title: A high pressure cell for supercritical CO₂ on-line chemical reactions studied with X-ray techniques.
abstract: A versatile high pressure X-ray sample cell has been developed for conducting in situ time-resolved X-ray scattering experiments in the pressure and temperature regime required (pressures up to 210 bars and temperatures up to 120 °C) for chemical reactions in supercritical fluids. The large exit opening angle of the cell allows simultaneous performance of SAXS-WAXS experiments. Diamond windows are used in order to benefit from the combination of maximum strength, minimal X-ray absorption and chemical inertia. The sample cell can also be utilised for X-ray spectroscopy experiments over a wide range of photon energies. Results of the online synthesis of a block copolymer, poly(methyl methacrylate-block-poly(benzyl methacrylate), by Reversible Addition-Fragmentation Chain Transfer (RAFT) in a supercritical CO2 dispersion polymerisation will be discussed. The contribution of the density fluctuations, as function of temperature, to the X-ray scattering signal has been quantified in order to allow appropriate background subtractions.
authors.affiliation: DUBBLE@ESRF, Netherlands Organisation for Scientific Research (N.W.O.), CS40220, 38043, Grenoble, Cedex 9, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Hermida-Merino
authors.affiliation: DUBBLE@ESRF, Netherlands Organisation for Scientific Research (N.W.O.), CS40220, 38043, Grenoble, Cedex 9, France.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Portale
authors.affiliation: School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Peter
authors.initials: P
authors.lastname: Fields
authors.affiliation: School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Richard
authors.initials: R
authors.lastname: Wilson
authors.affiliation: School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Simon P
authors.initials: SP
authors.lastname: Bassett
authors.affiliation: School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: James
authors.initials: J
authors.lastname: Jennings
authors.affiliation: School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Martin
authors.initials: M
authors.lastname: Dellar
authors.affiliation: Department of Chemical Engineering, University of Liège B6A, allée du 6 Août 3, B-4000 Liège, Belgium.
authors.forename: Cedric
authors.initials: C
authors.lastname: Gommes
authors.affiliation: School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Howdle
authors.affiliation: Element Six BV, P.O. Box 119, 5430 AC Cuijk, The Netherlands.
authors.forename: Benno C M
authors.initials: BC
authors.lastname: Vrolijk
authors.affiliation: DUBBLE@ESRF, Netherlands Organisation for Scientific Research (N.W.O.), CS40220, 38043, Grenoble, Cedex 9, France.
authors.forename: Wim
authors.initials: W
authors.lastname: Bras