Abstracts of 9th IGC Symposium 2020


Adam Voelkel, Poznan University of Technology, Faculty of Chemical Technology, Poznan, Poland

Knowledge of the properties of components expressed by means of physicochemical parameters is important in the processes of designing and manufacturing complex mixtures and formulations. It enables to assess the suitability of these materials for the intended applications. Very often, understanding and quantifying the interactions between components of a given system is crucial. This may be achieved by applying Inverse Gas Chromatography (IGC). These interactions are important in the processes of adhesion, wetting, swelling or dissolving.

In this lecture some unique applications of IGC will be presented.

We like to show application of IGC in the assessment of the physicochemical changes during the phenolic resins storage. Moreover, it makes possible to assess the chemical changes during storage at the different conditions quick and without need of the complicated sample preparation.

Hansen Solubility Parameters for a series of excipients used in the pharmaceutical industry might be successfully determined also for the solid, non-volatile pharmaceutically active materials. The influence of various factors on the value and precision of determining the solubility parameter using IGC will be also discussed.

Surface energy of bovine tooth tissues was examined by means of IGC. Results show that the type of tissue and occurring place have the greatest impact on the values of dispersive and specific (acid–base) component of surface energy and total value of surface energy.

This work was supported by 0912/SBAD/2000 grant.

Adam Voelkel, Katarzyna Adamska, Beata Strzemiecka

The interest of Solvay in Inverse Gas Chromatography: Examples of Applications

Julien Jolly, Ph.D., Research Scientist, Rhodia Laboratory of the future (Solvay Group), France

The surface chemistry of advanced materials industrially developed becomes more and more complex and requires the combination of different analytical techniques to better understand their properties. The inverse gas chromatography (IGC) is internally recognized as a powerful technique to provide quantitative and robust measurements. IGC is particularly adapted in our Silica Business Unit (mainly Tire and Oral Care applications) and several examples will be presented to demonstrate the interest of the IGC in the process optimization and innovation in the surface modification. Another interesting aspect of IGC concerning aging issues will be discussed. Finally, others applications in the field of coatings, dispersion and composites will be briefly exposed.

IGC Round Robin Test – Setup, Results, Interpretations and Best Practices

For the first time, a comparison of different IGC instruments and setups has been performed using one reference material. The results of twelve organizations from industry and universities, are being compared and deviations interpreted. It is not easy to start such an initiative of a round-robin test. In this case, Adscientis took the first step, organized tests and the data aggregation. The interpretations and recommendations have been – and still are – discussed by all participants.

Overall objective of this initiative is to learn from each other, discuss best practices and increase thereby the reliability and credibility of IGC as an analytical tool. The presentation will show the status of this process at the time being.

Mineral pigments surface properties: assessment of iGC-ID technique for leveraging quantitative knowledge and prediction of dispersion properties

HUYNH-EYSSAUTIER Joëlle, ESCOFFIER Antoine, VANDEGOOR Rondro, L’Oréal R&I, Aulnay sous Bois, France

Mineral pigments such as iron oxides and titanium dioxide are used in cosmetic formula for their color properties, and the quality of their dispersion is key for product performance. The dispersion medium can be fatty compounds, oils, water, emulsion… depending on the cosmetic product considered. In order to improve the dispersion of the pigments, dispersion medium can be tuned adjusting the oil polarity, or adding a surfactant in the aqueous phase. Another approach aims at selecting coated pigments. Raw materials suppliers offer a wide range of coating chemistries, but apart from the terms hydrophilic and hydrophobic, information is scarce on the surface properties of particles on a global aspect (as opposed to local techniques such as surface imaging). Based on this observation, we implemented a set of physico-chemical methods and found that iGC-ID (inverse gas chromatography at infinite dilution) was well suited to qualify and quantify the surface properties, and map the different coating propositions.

About 30 different pigments were analyzed through iGC-ID under the same protocol, for the determination of the dispersive component of the surface energy, nanoroughness, as well as polarity and acid/base character of the particle’s surface. It constitutes a start of knowledge database, making easier the search for properties/performance relationships. The final goal is to select the right coating based on its physico-chemical property.
While sharing the methodology, this presentation will also raise some questions to the iGC community on the application of the technique and its results, for an appropriate use of these precise data in the field of nanoparticles’ dispersion and formulation.