Preparation and characterization of polymer-modified template phases

Double layer membrane systems

By the addition of water-soluble polymers, the structure-forming behavior of lyotropic liquid-crystalline systems can be decisively influenced [6, 7, 10, 11, 13]. The introduction of charged polyelectrolytes leads, for example, to the formation of compact multilamellar vesicle structures with a strongly altered swelling capacity [8-10]. The addition of branched sugar-modified polyethyleneimines can induce a morphological transformation from a vesicle phase to a tubular network structure [12]. Polyampholytes, e.g. PalPhBisCarb, can produce similar effects of morphogenesis, as we have recently shown [14]. The resulting template phase can be used for the targeted production of flat gold nanotriangles [15].

Figure 1: Cryo scanning electron micrograph of a vesicular template phase


Cooperation:

  • Prof. S.E. Friberg (Clarkson University, USA)
  • Prof. Th. Hellweg (Universität Bayreuth)
  • Prof. E. Kleinpeter (Universität Potsdam)
  • Dr. D. Appelhans (Leibniz Institut, Dresden)

Selected Publications:

[6] S. Kosmella, J. Kötz, S.E. Friberg, R.A. Mackay
Interactions of Polyelectrolytes with the Lyotropic Liquid Crystalline System Na-dodecylsulfate / Decanol / Water
Ber. Bunsenges. Phys. Chem. 100 (1996) 6, 1059-1063 | DOI: 10.1002/bbpc.19961000659
[7] D. Ruppelt, J. Kötz, W. Jaeger, S.E. Friberg, R.E. Mackay
The Influence of Cationic Polyelectrolytes on Structure Formation in Lamellar Liquid Crystalline Systems
Langmuir 13 (1997) 3316-3319 | DOI: 10.1021/la9610258
[8] N. Bechthold, B. Tiersch, J. Kötz, S.E. Friberg
Structure Formation in Polymer-Modified Liquid Crystals
J. Colloid and Interface Sci. 215 (1999) 106-113 | DOI: 10.1006/jcis.1999.6199
[9] J. Kötz, B. Tiersch, I. Bogen
Polyelectrolyte induced vesicle-formation in lamellar liquid crystalline model systems
Colloid & Polymer Sci. 278 (2000) 164-168 | DOI: 10.1007/s003960050027
[10] Th. Hellweg, A. Brulet, D. Robertson, J. Koetz
Temperature and Polymer Induced Structural Changes in SDS/Decanol Based Multilamellar Vesicles
Phys. Chem. Chem. Phys. 4 (2002) 2612-2616 | DOI: 10.1039/B109643P
[11] D. Robertson, Th. Hellweg, B. Tiersch, J. Koetz
Polymer induced structural changes in lecithin/SDS-based multilamellar vesicles
J. Colloid and Interface Sci. 270 (2004) 187-194 | DOI: 10.1016/j.jcis.2003.09.013
[12] A. Köth, D. Appelhans, D. Robertson, B. Tiersch, J. Koetz
Use of Weakly Cationic Dendritic Glycopolymer for Morphological Transformation of Phospholipid Vesicles into Tube-like Network
Soft Matter (2011) 7, 10581-10584 | DOI: 10.1039/C1SM06439H
[13] J. Koetz, S. Kosmella
Polymers in lyotropic liquid crystalline systems
In A. Hubbard: Encyclopedia of Surface and Colloid Science
Second Edition; Taylor & Francis: New York (2006) 6, 5017-5022 | ISBN: 978-0-8493-9615-1
[14] N. Schulze, C. Prietzel, J. Koetz:
Polyampholyte mediated synthesis of anisotropic gold nanoplatelets,
Colloid & Polymer Sci. 294 (2016) 8, 1297-1304 | DOI: 10.1007/s00396-016-3890-y
[15] N. Schulze, D. Appelhans, B. Tiersch, J. Koetz:
Morphological transformation of vesicles into network structures by adding polyampholytes,
Colloids and Surfaces A 457 (2014) 326-332 | DOI: 10.1016/j.colsurfa.2014.06.007



Microemulsions

Polymers can be introduced into microemulsions, i.e. thermodynamically stable oil-water-surfactant-cosurfactant mixtures, without appearing of a macroscopic phase separation. Polymers can increase the stability of the surfactant film [16, 20], increase the phase area of the microemulsion [18, 19] or induce the formation of bicontinuous microemulsions [16, 17]. In the presence of polyampholytes, the stability of the surfactant film can be controlled by varying the pH value [3].

Cooperation:

  • Prof. S.E. Friberg (Clarkson University, USA)
  • Dr. A. Poghosyan (Academy of Science Yerevan, Armenia)
  • Prof. E. Kleinpeter (Universität Potsdam)

Selected Publications:

[16] T. Beitz, J. Kötz, S.E. Friberg
Polymer-modified Ionic Microemulsions Formed in the System SDS/ Water/ Xylene/ Pentanol
Progress in Colloid & Polymer Sci. (1998) 111, 100-106 | DOI: 10.1007/BFb0118117
[17] T. Beitz, J. Kötz, G. Wolf, E. Kleinpeter, S.E. Friberg
Poly(N-vinyl-2-pyrrolidone) and 1-Octyl-2-pyrrolidone modified Ionic Microemulsions
J. Colloid and Interface Sci. 240 (2001) 581-589 | DOI: 10.1006/jcis.2001.7635
[18] C. Note, J. Ruffin, B. Tiersch, J. Koetz
The influence of polyampholytes on the phase behaviour of microemulsions used as template for the nanoparticle formation
J. Dispersion Sci. And Technology 28 (2007) 1, 155-164 | DOI: 10.1080/01932690600992217
[19] M. Fechner, M. Kramer, E. Kleinpeter, J. Koetz
Polyampholyte-modified ionic microemulsions
Colloid & Polymer Sci. 215 (1999) 106-113287 (2009) 1145-1153 | DOI: 10.1007/s00396-009-2074-4
[20] A. Poghosyan, L. Arsenyan, H. Gharabekyan, S. Falkenhagen, J. Koetz, A. Shahinyan
The molecular dynamics simulation of inverse sodium dodecylsulfate (SDS) micelles in toluene/pentanol solute in absence and presence of poly(diallyldimethyl ammonium chloride) (PDADMAC)
J. Colloid and Interface Sci. 358 (2011) 175-181 | DOI: 10.1016/j.jcis.2011.01.091



Janus emulsions

Emulsifying two immiscible oil components and water in the presence of surface-active substances can produce so-called Janus emulsions. The following figure shows a photomicrograph of such a Janus emulsion.

Figure 2: Light microscopy of a Janus emulsion

First studies by Friberg et al. have shown that nonionic surfactants (e.g., Tween 80) can stabilize such oil1/oil2 drops [21-23]. Our investigations show that the droplet size can be reduced by the addition of phospholipids [24]. Moreover, it is possible to stabilize Janus emulsions in the presence of gelatin-chitosan mixtures [25]. The resulting Janus emulsions serve as a templating phase for the production of biodegradable scaffold materials [26].

Cooperation:

  • Prof. S.E. Friberg (Clarkson University, USA)

Selected Publications:

[21] S.E. Friberg, I. Kovach, J. Koetz:
Equilibrium topology and partial inversion of janus drops: A numerical analysis,
Chem. Phys. Chem. 14 (2013) 16, 3772-3776 | DOI: 10.1002/cphc.201300635
[22] H. Hasinovic, S. E. Friberg, I. Kovach, J. Koetz:
Destabilization of a dual emulsion to form a Janus emulsion,
Colloid & Polymer Sci. (2014) online | DOI: 10.1007/s00396-014-3263-3
[23] H. Hasinovic, S.E. Friberg, I. Kovach, J. Koetz:
Janus emulsions drops: equilibrium calculations,
J. Dispersion Sci. Technology 34 (2013) 1683-1689 | DOI: 10.1080/01932691.2013.763728
[24] I. Kovach, J. Koetz, S.E. Friberg:
Janus emulsions stabilized by phospholipids,
Colloids and Surfaces A 441 (2014) 66-71 | DOI: 10.1016/j.colsurfa.2013.08.065
[25] I. Kovach, J. Won, S.E. Friberg, J. Koetz:
Completely engulfed olive/silicone oil Janus emulsions with gelatin and chitosan,
Colloid & Polymer Sci. 294 (2016) 4, 705-713 | DOI: 10.1007/s00396-016-3828-4
[26] I. Kovach, J. Rumschöttel, S.E. Friberg, J. Koetz:
Janus emulsions mediated porous scaffold bio-fabrication,
Colloids and Surfaces B 145 (2016) 347-352 | DOI: 10.1016/j.colsurfb.2016.05.018