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The analytical technique micro-thermal analysis (μ-TA) will be introduced and evaluated. It combines the visualisation power of atomic force microscopy (AFM) and it's ability to image topography, phase shifts, friction, stiffness, and adhesion with the characterisation capabilities of thermal analysis (thermal conductivity, micro-differential thermal analysis and micro-thermo mechanical analysis) resulting in a characterisation of surfaces with respect to their thermal and thermo-mechanical properties. The scanning mode may be used for the inspection of surfaces with respect to their thermal properties using a scanner with an active thermal sensor (heater, height and thermal sensor) as probe (tip), simultaneously acquiring topography, thermal conductivity and thermal diffusivity images. A second mode gives the option to perform a ocal thermo-mechanical analysis of discrete areas of a few square microns (L-TMA and L-CA), and detects at the same time during heating in contact mode changes of the sensor position and the heat flow to the sample in a very short time. Any thermodynamic phase transition, connected with a change in mechanical properties (softening, expansion, melting) and thermal properties (heat of fusion, change of heat capacity) will thus be detected by both methods. Applications for the analysis of especialy soft materials are presented and critically discussed. Moreover, the use of the instrument for controlled surface treatment is demonstrated resulting in the creation of super smooth polymeric surfaces. Furthermore, attempts to determine thermal conductivity's on surfaces on a quantitative matter wil be presented and discussed.

This paper describes mechanical properties of polymer-clay nanocomposites with platelet and fibrous like nanoparticles evaluated on a of nano, meso and micro length scale. Platelet reinforced materials were found to display a mixed morphology consisting of intercalated and exfoliated regions. A better dispersion was obtained for fibrous clay nanocomposites where homogeneous distribution of single particles was achieved. The deformation behavior was investigated by in-situ XRD and SEM experiments during drawing; the macro-mechanical characteristics were extracted from tensile tests. The stiffness was found to increase in both platelet and fibrous clay nanocomposites. The presence of intercalated stacks in the latter resulted in a significant reduction in drawability, the better homogeneity of the fibrous clay systems allowed a reasonably high extensions.

Multifunctional nanocomposite coatings and bulk materials have been developed on the basis of a combination of purely organic, as well as hybrid organic-inorganic polymeric matrices and anisotropic synthetic and natural clays. The clays have been chemically modified in such a way that they became compatible to the polymeric matrices. Clay platelets may be separated by modification with an organic molecule that contains two or more charged functional groups. The cations or anions located between the clay sheets are exchanged with one of these organic functional groups, which results in the formation of clay platelets “coated” with charges, thereby causing a molecular dispersion. Depending on the nature of the organic molecule colored or colorless coatings and polymeric bulk materials, containing homogeneously dispersed separated clay platelets, have been obtained.While retaining the basic functional properties of the materials new and/or improved properties have been introduced. This concerns in particular improved barrier properties, such as a decreased permeability for oxygen and water, improved corrosion resistance and increased thermal stability.The composition of the wet coating systems is such that they can be properly applied and thermally or photo-chemically cured on various substrates such as glass, steel, aluminum and plastics. The bulk materials can be processed into final product shapes by conventional polymer processing techniques.

Polymer-layered silicate nanocomposites from polyamide-11 (PA-11) were prepared and the morphology and properties have been investigated in order to link the fundamental research field of polymer crystallization with the technical important field of composite materials. Semi-crystalline polymers are known to crystallize in different phases (e. g. monoclinic, hexagonal) forming chain-folded lamellar crystals. Depending on experimental conditions (e. g. temperature, pressure) the crystal size (lamellar thickness) affects the stability of these phases. The incorporation of layered silicates acting as hard walls into semi-crystalline polymers opens new possibilities to: i) study polymer crystallization in confined dimensions, and ii) provide materials from commodity or engineering polymers with enhanced properties. The effect of an external confinement introduced by highly anisotropic silicate layers of organically modified clay minerals on crystal growth and nanocomposite properties has been studied. The composites are prepared by in situ polycondensation of polyamides and/or blending via melt extrusion. The nanocomposites exhibit a homogeneous distribution of individual silicate layers at low clay contents. The lamellar thickening growth is reduced in polyamide crystallization due to the external constrained of the silicate layers in the host polymer. Furthermore these nanocomposites show a slightly enhanced thermal stability, tensile modulus and an increased elastic behavior over a broader temperature range. No distinct glass transition has been observed at highest clay contents.

Research in the area of biological renewable materials has shown that the main building blocks of life – carbohydrates, fats, proteins, and their derivatives - could substitute products from traditional nonrenewable sources. However its realization will need significant and continuous improvement of those materials. Problems of applications of bioplastics arise not only from the (price) competition with the highly developed synthetic polymers but also from their, up to now not sufficient property levels. Possibilities to decrease the hydrophilicity and to increase the values of mechanical properties so far are: i) application of hydrophobic coating(s); ii) blending with different, biodegradable synthetic polymers (polyesters) and iii) new ways of reactive extrusion of natural. A new possibility in this direction is seen in the creation of composite materials of thermoplastic organic biopolymer and nanoscopic inorganic particles incorporated on a molecular scale.This paper will show the results of the first experiments to get nano-scale starch/clay composites. The starch will be fully gelatinized and the modified clay can be dispersed homogeneously on a truly nanoscale. Therefore all requirements of a significant increase in mechanics and a decrease in permeability of this composite material are present.

In order to link the fundamental research field of polymer crystallization with the technical important field of composite materials polymer-layered silicate nanocomposites from polyethylene (PE) are prepared and their morphology and properties are investigated. The effect of an external confinement introduced by highly anisotropic silicate layers of organically modified clay minerals on crystal growth and nanocomposite properties has been studied. The prepared nanocomposites of organically modified clay minerals and PE exhibit not only a homogeneous distribution of individual silicate layers but also of tactoids. The isothermal crystallization rate of PE in the corresponding nanocomposite at 120 °C is increased in the composite material due to the action of the silicate layers. A significant effect on crystal phase has not been observed so far but from X-ray experiments, however the crystal size seems to be influenced. The thermal stability of the nanocomposites is significantly enhanced and the decomposition mechanism has been changed due to the presence of the layered silicates within the host polymer acting as a barrier for the diffusion of small molecules like oxygen. Due to the none permanent attachment of the polymer chains to the silicate surface the thermal-mechanical properties are only moderately enhanced at low temperature while the glass transition temperature remains unaffected.