Supercritical Polymerization
Monomers can be polymerized in supercritical solvents.
By supercritical conditions is meant that the combination of the monomers, comonomers, fluorocarbon, solvent, diluent and polymer product is not turbid at the polymerization pressure and temperature. Turbidity is present when light scattering is observed when shining a helium laser through the combination in a cloud point cell onto a photocell.
(RDC 9/14/2010)
Recent US Patents
6/22/2010
7,741,420
Polymer Production at Supercritical Conditions Composite
Brant has polymerized olefins in a superfluid using a fluorocarbon solvent with a hydrocarbon diluent, catalysts, activators and monomers.
Recent Journal Articles
The rate of polymerization in two loci reaction systems: VDF-HFP precipitation copolymerization in supercritical carbon dioxide
(2092–2101)Polymer Engineering & Science 51 #10 (2011)
Costaet al , Switzerland and Italy, found that when copolymerization of vinylidene fluoride (VDF) and hexafluoropropylene (HFP) is carried out in supercritical carbon dioxide (scCO2) under heterogeneous conditions, the reaction occurs both in the continuous CO2-rich phase and in the dispersed polymer-rich phase. The two phases being characterized by different values of reactant concentrations and kinetic parameters, one would expect that the reaction kinetics is affected by the polymer phase holdup in the reactor. However, the reaction rate is almost insensitive to the amount of produced polymer, at least at specific reaction conditions. (RDC 9/15/2011)