Thermoplastic Elastomers Containing Zinc Oxide as Antimicrobial Additive Under Thermal Accelerated Ageing

Styrene-ethylene/butylene-styrene (SEBS) copolymer- based thermoplastic elastomers (TPE) are applied in the production of household items used in places with conditions for microbial development. Metal oxides like zinc oxide (ZnO) and others can be added to the TPE composition to prevent microbial growth. The aim of this study is to evaluate the effect of thermal accelerated ageing on mechanical, chemical and antibacterial properties of SEBS-based TPE containing 0%, 1%, 3%, and 5% zinc oxide. Zinc oxide was characterized by laser diffraction, X-ray diffraction, superficial area, porosity and scanning electron microscopy. Both aged and unaged samples were analyzed by infrared spectroscopy, tensile at rupture, elongation at rupture, hardness and antimicrobial activity against Escherichia coli and Staphylococcus aureus. Following thermal exposure, a reduction of antimicrobial activity was observed. No significant difference was observed in the chemical and mechanical characteristics between aged and unaged samples.