Effect of copper nanoparticles on the properties of SEBS/PP compounds

This study evaluated the adoption of copper nanoparticles (CuNPs) as an antimicrobial agent in thermoplastic elastomer compounds (TPEs) based on styrene-(ethylene-butylene)-styrene triblock copolymer (SEBS) and polypropylene (PP) for use in the fabrication of automotive air-conditioning systems. The nanocompounds were prepared using a co-rotating double screw extruder and CuNPs were pre-dispersed in polypropylene at weight proportions of 0%, 0.6% and 1.0%. The physical (density), mechanical (tensile and hardness), thermal (differential scanning calorimetry and thermogravimetry) and antimicrobial properties were evaluated on injection molded plates. The antimicrobial properties were evaluated for the bacteria Staphylococcus aureus and Escherichia coli and fungal species commonly found in automotive air conditioners. The results from antibacterial tests showed a reduction of 99.9% in counts of both bacteria tested. There was no fungal growth on the loaded TPE surface. At the tested levels, the addition of CuNPs did not cause significant variations in the TPE properties evaluated.