Chair Polymer Chemistry
Surface Polarity

Functionalization and Analytics of Surfaces
- Determination of Surface Polarity using Solvatochromism -


During the last 15 years our group developed a method for determining the polarity of particles. Herefore we use solvatochromic probe molecules which alter their UV/vis absorption in a characteristic way after adsorption onto a surface. From this variation of the UV/vis absorption band one can calculate a parameter which describes a particular surface property.

The basis of this approach is the multi parameter model of Kamlet and Taft. According to that, three parameters are used to characterize a surface:

α = hydrogen bond donating ability resp. acidity
β = hydrogen bond accepting ability resp. basicity
π* = dipolarity/polarizability

For the determination of these parameters three solvatochromic probes have been recognized to be particularly suitable, which are susceptible to one of the parameters at a time.



Selected publications on this topic:


Probing Surface Polarity using Merocyanine-type Dyes derived from Barbituric Acid.
S. Seifert, A. Seifert, K. Hofmann, T. Rüffer, G. Brunklaus, H. Lang, S. Spange, New Journal of Chemistry 2012, 36, 674-684.
DOI: http://dx.doi.org/10.1039/C2NJ20835K, ISSN: 1144–0546.

Adsorption of Poly(vinyl formamide-co-vinyl amine) (PVFA-co-PVAm) Polymers on Zinc, Zinc Oxide, Iron, and Iron Oxide Surfaces.
S. Seifert, F. Simon, G. Baumann, M. Hietschold, A. Seifert, S. Spange, Langmuir 2011, 27, 14279–14289.
DOI: 10.1021/la203479n

Internal and External Acidity of Faujasites As Measured by a Solvatochromic Spiropyran.
I. Kahle, S. Spange, J. Phys. Chem. C 2010, 114(36), 15448–15453.
DOI: 10.1021/jp1048106

A Solvatochromic Dye for Probing Significantly the Dipolarity/Polarizability of Acidic Environments.
S. Spange, R. Sens, Y. Zimmermann, A. Seifert, I. Roth, S. Anders, K. Hofmann, New J. Chem. 2003, 27, 520–524.

Adsorption of Polymers on Inorganic Solid Acids Investigated by Means of Co-adsorbed Solvatochromic Probes.
S. Prause, S. Spange, J. Phys. Chem. B 2004, 108, 5734–5741.

Surface Polarity of Dimethylsiloxane-Grafted Silica Particles.
S. Prause, S. Spange, H. Barthel, Macromol. Chem. Phys. 2005, 206, 364–371.