Thermo-physical characteristics, mechanical performance and long-term stability of high temperature latent heat storages based on paraffin-polymer compounds

Different polyolefin matrix materials were melt-blended with high-molecular weight paraffin waxes as phase change materials (PCM) on a lab-scale extruder. Afterwards, the compounds were converted into latent heat storage plates via compression molding. Detailed morphological investigations of the functional materials with Differential Scanning Calorimetry and Small Angle X-ray Scattering revealed various types of interaction between the applied components. Distinct correlations between the material formulation, the resulting overall compound morphology and the mechanical characteristics of the compounds were established. Moreover, a high long-term stability in terms of latent heat storage capacity, morphology and mechanical properties was ascertained, which emphasizes a high application potential of the functional materials. However, since the mechanical characteristics of the compounds deteriorated significantly upon the melting of the PCM (i.e. beginning storage of latent heat), latent heat storages in the form of polymeric compounds are not applicable as load-bearing component.