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Switchable Surfactants and Coatings

“Switchable” (adj.) able to reversibly switch “on” and “off”, or switch between one property and another, when a trigger is applied. Imagine a solvent that could switch reversibly from one kind of liquid to a very different kind of liquid, upon command. We have found three classes of switchable solvents, as shown below. For a review of CO2-switchable solvents, surfactants and other materials, see Energy & Env. Sci., (2012) 5, 7240.
1. Switchable Surfactants

Imagine a surfactant that stabilizes emulsions but could switch reversibly to a demulsifier, upon command. Emulsions could be stabilized while they are wanted and then destabilized when the emulsion is no longer wanted. We have found molecules that are cationic surfactants in the presence of CO2 but convert to demulsifiers if the CO2 is flushed away with air. We have also found molecules that are anionic surfactants in the absence of CO2 but are switched off and precipitated if CO2 is introduced. This technology has great potential for applications in the energy industry, cleaning, fine chemical manufacture, polymers, coatings, soil washing and many other areas.

Key references are listed below.

2. Switchable Particles and Surfaces

Solid particles that have CO2-switchable groups on the surface (either covalently attached or via noncovalent interactions) can be switched reversibly between one state that is neutral, hydrophobic, water-repelling and another state that is charged, hydrophilic, and water-absorbing. This can be used to make suspensions switch between stable and coagulated. It can also be used to make drying agents switch between water-absorbing (for the drying of organic liquids) and water-repelling (for the regeneration of the drying agent). Similarly, surfaces such as membranes can be made to alternate between hydrophilic and hydrophobic states.

This research is being performed in collaboration with Prof. Cunningham of Chemical Engineering at Queen’s.

Key references are listed below.

3. Switchable Coatings
Because oil- or solvent-based coatings (e.g. paints, varnishes, sealants) emit volatile organic compounds (VOCs), replacement with aqueous coating formulations is desirable. However, water-based (latex) coatings which are dispersions of polymer particles, are out-performed by solvent-based coatings in hardness, durability, gloss and cold-weather application. The challenge with latexes is that discrete polymer particles must coalesce to form a complete film, a complex process that often leads to imperfections in the coating. Our results show that CO2-responsive copolymers can form the basis of a waterborne coating in which the polymer is fully dissolved before application and yet water-resistant after application to a surface. These polymers are insoluble in neutral water, but dissolve fully in carbonated water. When a carbonated solution of polymer is cast onto a substrate, the subsequent loss of CO2 and water by evaporation results in a clear, continuous water-resistant coating. In the photo, a traditional latex paint, once dried, is damaged by exposure to water (top row) while our carbonated-water-based paints (bottom and middle rows) are water-resistant. These new coatings may retain the VOC-free advantage of water-based coatings while eliminating the need for coalescence of particles.


About Switchable Surfactants
  • E. Ceschia, J. R. Harjani, C. Liang, Z. Ghoshouni, T. Andrea, R. S. Brown, and P. G. Jessop “Switchable Anionic Surfactants for the Remediation of Oil-Contaminated Sand by Soil Washing”, RSC Advances, 2014, 4, 4638-4645.
  • L. M. Scott, T. Robert, J. R. Harjani, and P. G. Jessop “Designing the Head Group of CO2-Triggered Switchable Surfactants”, RSC Advances, 2012, 2, 4925-4931.
  • C. Liang, J. R. Harjani, T. Robert, E. Rogel, D. Kuehne, C. Ovalles, V. Sampath, and P. G. Jessop “Use of CO2-Triggered Switchable Surfactants for the Stabilization of Heavy Crude Oil-in-Water Emulsions”, Energy & Fuels, 2012, 26, 488-494.
  • T. Arthur, J. Harjani, P. G. Jessop, and P. V. Hodson “Effects-Driven Chemical Design: The Acute Toxicity of Switchable Surfactants to Rainbow Trout can be Predicted from Octanol-Water Partition Coefficients”, Green Chem., 2012, 14, 357-362.
  • J. R. Harjani, C. Liang, P. G. Jessop, “A Synthesis of Acetamidines”, J. Org. Chem., 2011, 76, 1683-1691.
  • Y. Liu, P. G. Jessop, M. Cunningham, C. A. Eckert, C. L. Liotta, “Switchable Surfactants” Science, 2006, 313, 958-960.
About Switchable Particles and Surfaces
  • A. Darabi, A. R. Shirin-Abadi, R. Abbas, S. Avar, P. Jessop, M. Cunningham, “Surfactant-Free Emulsion Copolymerization of Styrene and Methyl Methacrylate for Preparation of Water-Redispersible Polymeric Powders”, J. Polym. Sci. A: Polym. Chem., 2018, 56, 2376-2381.
  • J. Glasing, P. G. Jessop, P. Champagne, W. Y. Hamadd, M. F. Cunningham, “Microsuspension Polymerization of Styrene using Cellulose Nanocrystals as Pickering Emulsifiers: on the Evolution of Latex Particles”, Langmuir, 2020, in press.
  • A. R. Shirin-Abadi, M. Gorji, S. Rezaee, P. G. Jessop, M. F. Cunningham “CO2-Switchable-Hydrophilicity Membrane (CO2-SHM) Triggered by Electric Potential: Faster Switching Time along with Efficient Oil/Water Separation”, Chem. Commun., 2018, 54, 8478-8481.
  • J. Glasing, P. G. Jessop, P. Champagne, M. F. Cunningham, “Graft-modified cellulose nanocrystals as CO2-switchable Pickering emulsifiers”, Polymer Chem., 2018, 9, 3864-3872.
  • J. Glasing, J. Bouchard, P. G. Jessop, P. Champagne, and M. F. Cunningham, “Grafting well-defined CO2-responsive polymers to cellulose nanocrystals via nitroxide-mediated polymerisation: effect of graft density and molecular weight on dispersion behaviour”, Polymer Chem., 2017, 8, 6000-6012.
  • O. Garcia-Valdez, T. Brescacin, J. Arredondo, J. Bouchard, P. G. Jessop, P. Champagne, and M. F. Cunningham, “Grafting CO2-responsive polymers from cellulose nanocrystals via nitroxide-mediated polymerisation”, Polymer Chem., 2017, 8, 4124-4131.
  • J. Arredondo, P. G. Jessop, P. Champagne, J. Bouchard, M. F. Cunningham, “Synthesis of Carbon Dioxide Responsive Cellulose Nanocrystals by Surface-Initiated Cu(0)-Mediated Polymerisation”, Green Chem., 2017, 19, 4141-4152.
  • A. R. Shirin-Abadi, P. G. Jessop, M. Cunningham, “In situ use of aqueous RAFT prepared poly (2-(diethylamino)ethyl methacrylate) as a stabilizer for preparation of CO2 switchable latexes”, Macromol. React. Eng., 2017, 11, 1600035.
  • A. Darabi, J. Glasing, P. G. Jessop, M. Cunningham, “Preparation of CO2-Switchable Latexes Using Dimethylaminopropyl Methacrylamide (DMAPMAm)”, J. Polym. Sci. A: Polym. Chem., 2017, 55, 1059-1066.
  • A. R. Shirin-Abadi, R. Abbas, A. Darabi, P. G. Jessop, M. Cunningham, “Tuning the aggregation and redispersion behavior of CO2-switchable latexes by a combination of DMAEMA and PDMAEMA-b-PMMA as stabilizing moieties,” Polymer, 2016, 106, 303-312.
  • X. Su, K. Nishizawa, E. Bultz, M. Sawamoto, M. Ouchi, P. Jessop, M. Cunningham, “Living CO2 Switchable Latexes Prepared Via Emulsion ATRP And AGET Miniemulsion ATRP”, Macromolecules, 2016, 49, 6251-6259.
  • A. Darabi, P. G. Jessop, and M. F. Cunningham, “CO2-responsive polymeric materials: Synthesis, self-assembly, and functional applications”, Chem. Soc. Rev., 2016, 45, 4391-4436.
  • Y. Y. Lau, T. Andrea, P. G Jessop, and J. H. Horton, “The Effect of Switchable Additives on Colloidal Interactions Found in Oil Sands as Measured by Chemical Force Spectrometry”, Can. J. Chem., 2016, 94, 482-489.
  • M. Cunningham and P. G. Jessop, “An introduction to the principles and fundamentals of CO2-switchable polymers and polymer colloid”, Eur. Polymer J., 2016, 76, 208-215.
  • H.-D. Wang, P. Jessop, J. Bouchard, P. Champagne, M. Cunningham, “Cellulose Nanocrystals with CO2-Switchable Aggregation and Redispersion Properties”, Cellulose, 2015, 22, 3105-3116.
  • A. Darabi, P. Jessop, M. Cunningham, “One-Pot Synthesis of Poly((Diethylamino)ethyl Methacrylate-co-Styrene)-b-Poly(Methyl Methacrylate-co-Styrene) Nanoparticles via Nitroxide-Mediated Polymerization”, Macromolecules, 2015, 48, 1952-1958.
  • A. Shirin-Abadi, A. Darabi, P. Jessop, M. Cunningham, “Preparation of Redispersible Polymer Latexes using Cationic Stabilizers based on 2-Dimethylaminoethyl Methacrylate Hydrochloride and 2,2′-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride”, Polymer, 2015, 60, 1-8.
  • X. Su, P. G. Jessop, M. F. Cunningham “Switchable Surfactants at the Polystyrene-Water Interface: Effect of Molecular Structure”, Green Materials, 2014, 2, 69-81.
  • E. Ceschia, J. R. Harjani, C. Liang, Z. Ghoshouni, T. Andrea, R. S. Brown, and P. G. Jessop “Switchable Anionic Surfactants for the Remediation of Oil-Contaminated Sand by Soil Washing”, RSC Advances, 2014, 4, 4638-4645.
  • X. Su, C. Fowler, C. O’Neill, J. Pinaud, E. Kowal, P. Jessop, M. Cunningham, “Emulsion Polymerization using Switchable Surfactants: A Route Towards Water Redispersable Latexes”, Macromol. Symp., 2013, 333, 93-101.
  • J. Jiang, Y. He, L. Wan, Z. Cui, Z. Cui and P. G. Jessop, “Synthesis of CdS nanoparticles in switchable surfactant reverse micelles”, Chem. Commun., 2013, 49, 1912-1914.
  • C. O’Neill, C. Fowler, P. G. Jessop, and M. F. Cunningham “Redispersing Aggregated Latexes Made with Switchable Surfactants”, Green Materials, 20131, 27-35.
  • Pinaud, J.; Kowal, E.; Jessop, P.; Cunningham, M., “2-(Diethyl)aminoethyl methacrylate as a CO2-switchable co-monomer for the preparation of readily coagulated and redispersed polymer latexes”, ACS Macro Lett., 20121, 1103-1107.
  • C. I. Fowler, P. G. Jessop and M. F. Cunningham, “Aryl Amidine and Tertiary Amine Switchable Surfactants and Their Application in the Emulsion Polymerization of Methyl Methacrylate”, Macromolecules, 2012,45, 2955-2962. DOI: 10.1021/ma2027484
  • M. Mihara, M. Cunningham, and P. G. Jessop “Redispersible Polymer Colloids using Carbon Dioxide as an External Stimulus”, Macromolecules201144, 3688-3693.
  • C. I. Fowler, C. Muchemu, R. E. Miller, L. Phan, O’Neill, C., M. F. Cunningham, and P. G. Jessop “Emulsion Polymerization of Styrene and Methyl Methacrylate using Cationic Switchable Surfactants”, Macromolecules201144, 2501-2509.
About Switchable Coatings
  • J. Ho, B. Mudraboyina, C. Spence-Elder, R. Resendes, M. F. Cunningham, P. G. Jessop, “Water-borne coatings that share the mechanism of action of oil-based coatings”, Green Chem., 2018, 20, 1899-1905.