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The Conference has been organised
by three Societies from Germany and Switzerland with the goal of interactions
and discussions between industry and academia. The Society eurostar-science promotes
such interrelations since 1992 with seven conferences in Europe.
One group of lecturers presented
reviews about development projects for new materials, composites,
multifunctional compounds, polymers and additives. Another group of lecturers
gave inside views about specific production processes mainly for new materials.
The third group has been dealing with analytical procedures and methods applied
to the characterisation of materials and substances. Most of the poster
presentations pointed to specific experimental results, to evaluation methods of
analytical data and also to methodological aspects.
The NETZSCH-GEFTA Award has
been dedicated to Marek Maciejewski for the development of the Pulse Thermal
Analysis (Pulse TA ®), a procedure which allows a variety of
analytical measurements and physicochemical investigations. Examples are the
calibration for a specific molecule or a group of molecules for mass
spectrometers, especially also of DTA-TG-MS and TG-FTIR. Quantitative
spectroscopic measurements are performed with comfortable handling. Gas - solid
reactions can be studied with this procedure as a screening method for catalytic
reactions and also processes of chemisorption and physisorption are
straightforward elucidated.
The Award has been presented to Marek Maciejewski at the Opening Ceremony of the
Conference by Michael Feist, Humboldt-University, Berlin and Wolf-Dieter
Emmerich, NETZSCH Gerätebau GmbH, Selb.
Aspects of new materials and
their characterisation on the basis of C/C-SiC with applications for vehicles
used in the aerospace and in the stratosphere had been outlined by M. Friess,
Deutsches Zentrum für Luft- und Raumfahrt, Stuttgart, and also by H. -P. Maier
and G. Neuer, University of Stuttgart. Additional applications of these
materials are existing also for high temperature exposures in industry.
Multifunctional, laminated,
metallic materials processed by thixoforming at high temperatures around 1400°C
in partially liquid metallic phases are revealing for well-selected alloys
extremely high values for the heat conductivity. Surface protection for chemical
and tribological degradation processes can be achieved with ceramic layers. Th.
Horning, RWTH Aachen, has presented the project, which is carried out in
cooperation with several institutes. The characterisation of these materials by
thermal analysis was a main point of this lecture.
Intensity modulated light sources
can be used to gain valuable data about the surface properties of thin surface
layers in respect to heat conductivity and to temperature gradients even in
dimensions of a few micrometers. Substance inhomogeneities or mechanical
distortions at the surface of materials can be made visible. The observable
depth of the layers can be adjusted by changing the modulation frequency. M.
Rohde, Forschungszentrum Karlsruhe, Eggenstein, has demonstrated the development
of this method and he discussed selected examples.
R. Hässler, Institute for
Polymer Research, Dresden, was an invited lecturer of the European Society for
Applied Physical Chemistry. He presented a microthermal method (μTA ™)
which combines an atomic force microscope with a thermoanalytical device,
similar to a DTA or to a TMA. The instruments enable a study of surface
properties with a high geometric resolution and in dimensions of a few
micrometers. Some examples for laminated materials were outlined.
M. Oechsle of dmc2 ,
Hanau gave a review about Platiline ®, a product with applications
in the area of catalytic processes as well as for moulding processes such as for
glasses with high surface qualities. Additional benefits in the use of Platiline
® are the lower amount of capital bound in the production processes and
the possibility of recycling the platinum.
Investigations about temperature
stress and UV-irradiation applied to samples of polyoxy-methylene (POM), have
been outlined by Mrs. V.-M. Archodoulaki, University of Technology, Vienna. The
material is broadly used in indoor applications of cars. Screening tests, e.g.
oven-storage and the Xenon test were applied to study the stability in
processing and application. Additionally, different thermoanalytical methods
revealed a high sensitivity for the investigation of the degradation compared
with the screening methods applied.
The Institute for Ecological
Chemistry, Neuherberg (München), was presented with several research
activities, namely analytical investigations about additives, stabilizers and
flame retardants. Qualitative and quantitative results for different groups of
additives and polymers were outlined by A.A. Kettrup, G. Matuschek, and N.
Milanov.
Immersion painting by
electrolysis and the consecutive tempering process are production pathways of
choice in the car industry. The characterisation of painting systems and the
study of the kinetic reactions during tempering are straightforward achieved
with measurements using DSC, DTA, DMA, TG, and TG-FTIR instruments. An insight
view of the development work by the BMW Group in Dingolfing has been outlined by
Ch. Froschauer.
Additional information about the
tempering process of these painting systems in laboratory experiments has been
discussed. The importance of applying software programs, namely KINETIK®,
ChemRheo ®, and VPS/DRY for such a development had been outlined. The
cross-linking process of the varnish and the geometrical distribution of
temperature-time situation over the whole car chassis were visualised with
colour changing sequences. Mrs. Lang, CAD-FEM GmbH, Grafing (München) and J.
Opfermann, Netzsch Gerätebau GmbH, Selb presented the interesting development
work.
The synthesis and thermodynamic
characterisation of polymer materials performed with a reaction calorimeter
called High Pressure Scanning Transitometry (HPST) has been reported by J. -P.E.
Grolier, University Blaise Pascal, Aubière, France. Professor Grolier has been
an invited lecturer by the European Society for Applied Physical Chemistry. The
reaction calorimeter is an instrument as well as a reactor. Temperature,
pressure, and volume can be changed and by this way the heat capacities, the
enthalpy changes, the compressibility, and the expansivity are determined of a
given sample. Another route enables the synthesis of new materials. An example
has been outlined for the high-pressure production of a polymeric material with
a rather small distribution of the molecular weight. The development of
taylor-made polymers by the variety of the independent parameters and the vast
variation of the reactor instrument used is straightforward achieved with this reaction calorimeter.
Mrs.
U. Bentrup illuminated the oxidation process of substituted aromatic compounds
such as p-methoxytoluene on a V2O5 catalyst and also on
phases of the formula MxV2O5-x with M as an
alkali metal. The adsorption on the surface of the catalysts and its reactivity
has been studied with TG, DTA, and mass spectroscopy.
The characterisation of partially
crystalline thermoplastic materials using among other methods dynamic mechanical
thermal analysis and temperature modulated DSC (TMDSC) has been demonstrated by
Ch. Schick, University of Rostock. Step Scan DSC as an additionally development
has been explained, a method which had been introduced many years ago as a
step-heating procedure applied for the purity measurement by DSC. TMDSC enables
heat capacity measurements better than 1%. The enthalpy calibration of DSC
instruments using Indium and several other reference substances - see S.M. Sarge
"DSC-Calibration with materials certified by the PTB, Braunschweig" -
enable also to achieve enthalpy values better than 1%.
Ch. Schick presented as an
example the structural relaxation of non cross-linked interlaced molecular
chains for polystyrene. Such an energetic driven relaxation can be observed in
cooling an amorphous or partially amorphous sample from a high temperature into
the glass transition region. Schick found at the glass transition temperature a
value for the relaxation time of about 5 minutes. E. Marti reported in his
lecture "Characterisation of Polymers by Thermoanalytical Methods"
also for polystyrene results obtained by G. Rehage, Technical University
Clausthal. Rehage measured the change of the refraction index also under
isothermal conditions above and below the glass transition temperature of 89
oC. The evaluation of an approximated relaxation time gave in a good
agreement with Ch. Schick a value of 10 minutes. Interesting is the fact that
the molecular chains of polystyrene in an amorphous sample are revealing only 12
K under the glass transition temperature according to Rehage a
relaxation time of 1 year. This finding can be explained by the drastic decrease
of the mobility in the "amorphous solid state" compared to the
decrease existing in the "amorphous liquid state" in appoaching the
glass transition region. A similar situation is observed by the mobilty in the
corresponding solid phase. An example for this mobility are the highly
different self-diffusion coefficients of water molecules in liquid water and in
ice. The fact, that such measurements becoming accessible
by DSC, not below the glass transition temperature, but within the glass
transition region is a consequence of the extraordinary improved sensitivity of
DSC. Such instrumental developments will further enlarge the frame of the main
instrument of thermal analysis, namely the DSC.
In addition, several
manufacturers of instruments presented and discussed the newest instrumental
developments as well as evaluation procedures.
Solvias AG, Basel distributed information about the frame of the offered
services and the service capabilities.
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Dr.
Erwin Marti
