The Effect of Particulate Fillers on Hardness of Polymer Composite

The analysis of polymeric composites can be quite challenging because the samples are often consist of complex nature due to the presence of various groups of additives, compounding ingredients, and fillers. In this contribution, changes of hardness of Polypropylene (PP) composites during and after exposure materials to UV chamber and low temperatures were investigated. The particulate fillers talc and chalk in weight fraction from 10 to 50 % and montmorillonite (MMT) in weight fraction 4 % were used as fillers in the polypropylene matrix. The composites were mixed in the extruder while the length, diameter of screw, as well as number of grooves in the feed zone were changed. Influence of ageing – UV radiation and low temperature was examined by change of Shore hardness after 360 h and 720 h of exposure. According to the performed tests we can conclude that tested materials may be exposed to UV radiation and low temperature of -20 ºC without significant changes of hardness