SOLUTION CHEMISTRY REGENSBURG Werner Kunz Institut für Physikalische und Theoretische Chemie Universität Regensburg

1. Solvents, Hydrotropes and Ions a Challenge for COSMO-RS UNESCO World Culture Heritage SOLUTION CHEMISTRY REGENSBURG Werner Kunz Institut für Physikalische und Theoretische Chemie Universität Regensburg

2. S C R Spontaneous self-organisation: Characterization, conception and practical application of complex nano-structured liquids and their interfaces define the central research interests of the Regensburg Solution Chemistry Group.

3. Solubilisation Phenomena Electrolyte Phenomena Specific ion effects PROPERTY STRUCTURE SOLUBILITY Examples: Solvosurfactants, hydrophobic polymers in solution, microemulsions Examples: Influence on Phase Diagrams, Proteins, pH Reaction Phenomena Interfacial Phenomena MEDIUM REACTIVITY STRUCTURE ADSORPTION Examples: Enzymes in µ-emulsions, salt solutions at 200°C Examples: Washing-off of polymers at solid interfaces, emulsions, microemulsions

4. SCR A selection of our activities  Blastulae vesicles • Specific ion effects in nature and technology • Ionic surfactant liquids and liquid catanionics (patent with BASF) • Hydrotropes – Solvosurfactants – Green Solvents and Surfactants – Microemulsions • (with L’Oréal, Novartis, BASF, Procter & Gamble, etc. etc.) • Solubility of hydrophobic molecules in water • Sustainable Chemistry: reactions in aqueous solutions at around 200°C • Spontaneous vesicle formation – understanding and applications • Developing of new mosquito attractants and repellents • Development of new porous gels, membranes and ceramics with narrow • pore-size distributions for technical and medical devices (patent) • Making interfaces human compatible and antibacterial • Towards chiral lime – understanding and design of biomorphs Biomorphs BaCO3 + Silicate + LaCl3 Highly ordered ceramics February 2009

5. S K H S K H SKH A selection of our activities • Development of new solvents for industrial use (Solubilizers, Co-Solvents, IL, Lubricants, Green Solvents etc.) • Development of new environment friendly cleaning and degreasing agents • Recovering and retreatment of solvents from car industry • Use of microemulsions for pharmaceutical or cosmetical products • Development of PEG-free cosmetics • Development of deodorizing agents for industry and agriculture February 2008

6. S K H Your Partner in Applied Chemistry and Technology Contact: SKH-GmbH, Königbacher Strasse 17 D-94496 Ortenburg-Dorfbach http://www.skh-gmbh.de info@skh-gmbh.de

7. from sustainable resources from sustainable resources in the Future: SOUSTAINABLE CHEMISTRY and DeepEutectic Mixtures Green Solvents Green Ionic Liquids in aqueous solutions from sustainable resources Green Reactions Green Surfactants and Hydrotropes

8. Green and/or sustainable ILs I Werner Kunz, L'Oréal, Mars 2009

9. Green and/or sustainable ILs II Werner Kunz, L'Oréal, Mars 2009

10. plus: BIOMOPRPHS (mixtures of silicate and carbonate)

11. SXS Solvo-Surfactants low structuring high structuring Solvents Solvo-Surfactants Surfactants ether propylene glycol non-ionic surfactants toluene alkyl ethers cholates water ionic surfactants DPnP

12. chemical formula: Polypropyleneglycolmonoalkylethers i = 1, 3 and 4 j = 1, 2 and 3 Commercial names: Dowanols®, Arcosolv®

13. Applications • in paints as solvents • in cleaning products • in cosmetic and perfume industries as coupling agent • in crop science as solvents • in ink as solvents

14. Biometabolisation

16. Temperature °C 2F LCST 1F water CiPOjCiEOj LCST CiPOj  j  CiEOj  Schematic Phase Diagram

17. Cloud point versus the PGAE mass fraction for: PnP (■), DPnP (●) and TPnP (▲) /water systems Cloud point versus the PGAE mass fraction for: PnB (■), DPnB (●), TPnB (▲) and PTB (▼) /water systems

18. We studied the aqueous solubilization of a hydrophobic dye DR-13 by co-solvents and hydrotropes (at 25°C). Characteristics of a Hydrotrope • A hydrotrope is a small water-soluble non-micelle-forming or weakly micelle-forming compound with a polar head and an unpolar tail that usually prevents the formation of gel formation in surfactant solutions.

19. exponential increase in the solubilization • CiPOj efficient hydrotropes • Hydrophobic extent: major factor influencing the hydrotropic efficiency

20. Solubilisation Efficiency of Surfactants and Hydrotropes SDS Hydrotropes The optical density (O.D.), proportional to the amount of dissolved DR-13 dye, versus the molar concentrations of SDS in water. This curve is compared to the ones obtained with SXS and C3EO1

21. Correlations • The Solubilisation Efficiency roughly correlates • with the size of the hydrophobic part of the hydrotrope • It correlates well with the hydrotrope’s shift “efficiency” • of the cmc of SDS • It does not correlate at all with the solubility in the neat hydrotrope • or with the solubility of the hydrotrope in water

22. Hydrotropes or Solvo-Surfactants are small (therefore rapidly • diffusing) molecules with excellent solvent properties and a certain • surface activity. • They have also excellent co-solvent and co-surfactant activities. • They can be used to induced a desired and adjustable • temperature dependence in ionic micro-emulsions. • “Nature do not like surfactants” ACKNOWLEDGEMENTS Pierre Bauduin, Didier Touraud StigFriberg and many others (Barry Ninham, Audrey Renoncourt, Laurent Wattebled …)

24. Future Challenge: • COSMO-RS for short and long-range interactions • in Deep Eutectic Mixtures

25. Future Challenge: • COSMO-RS combined with mesoscale simulations • for colloidal systems

26. Future Challenge: • COSMO-RS for short and long-range interactions • in aqueous salt solutions

27. Activity coefficients of simple electrolyte solutions soft-soft  association hard-hard  association See book of Robinson and Stokes

28. Activity coefficients of simple electrolyte solutions

29. Kim Collins (2004): Li+ Na+ K+ Rb+ Cs+ NH4+ hard soft reason: charge density carboxylate phosphate sulphonate sulphate

30. Dozens of experiments can be explained now and others • predicted: • cation affinity to ion-exchange resins • membrane potentials • electrophoreticmobilities of colloids • ion-transport phenomena • swelling of hydrogels • counter-ion binding to fatty acids • counter-ion binding to polyelectrolytes and phospholipids • counter-ion binding to micelles • Example: • B.W. Ninham, S. Hashimoto, J.K. Thomas • Unusualbehaviourofhydroxidesurfactants • Journal ofColloid & Interface Science 95 (1983) 594-596 • cmc (DDA+ OH─) ≈ 2 cmc (DDA+Br─) explainedwith • „hydrationforces“. • Ourexplanation: OH─ does not comeintoclosecontactwith DDA+

31. Langmuir 23(20) (2007) 10074-80 soft-soft hard-hard Cook et al., J. Chromatog. A 997 (2003) 13

32. Thank You ! Merci! DANKE

33. Have fun with COSMO-RS ! All the best for Dr. Klamt and

35. Permanent researchstaff: W. Kunz, H. Motschmann, H. Gores, R. Buchner, R. Neueder, D. Touraud in summer 2004 26 PhD students, 12 master students,several postdocs, guest professors, three engineers, technical and administrative staff

36. The Solubilisation Efficiency roughly correlates with the size of the hydrophobic part of the hydrotrope

37. Correlation of Surface Tension Lowering and Solubility C3PO1 Vm = 134.3 cm3/mol

38. Co-surfactant properties:in microemulsion systems Interests:useofmicroemulsions: • asreactionmediawithfacilitatedseparationandpurificationsteps • in extractionprocesses • Non-ionic polyethoxylated surfactants CiEOj form efficient temperature sensitive microemulsions (sometimes without co-surfactant) but as reaction medium: the purification of the reaction product is intricate. • Ionic surfactants form microemulsions which show lower temperature sensitivity, moreover in nearly all the cases a co-surfactant is needed. • The idea is to draw advantage from the temperature dependence behavior of CiPOj to design anionic temperature sensitive microemulsions.

39. SDS C4PO3 dodecane water Co-surfactant property:in microemulsion systems • Strategy to design anionic temperature sensitive microemulsions composed of water/SDS/C4PO3/dodecane 1/6.26 PS=0.5 at 21°C