Mechanical and Antibacterial Properties of Treated and Untreated Zinc Oxide filled UHMWPE Composites

Treated and untreated zinc oxide (ZnO) particulate reinforced ultra high molecular weight polyethylene (UHMWPE) composites were prepared using hydraulic hot press. The effects of the ZnO filler loading on tensile and antibacterial properties of the composites were investigated. The ZnO surfaces were treated with silane coupling agent (3-APTES) and were characterized using FTIR. The influences of ZnO content on tensile behavior of the composites were investigated. The tensile fracture surfaces of the ZnO-filled UHMWPE composites were characterized using SEM. Antibacterial property was tested against two common human body bacteria, that is, Escherichia coli and Staphylococcus aureus. The results showed that the tensile modulus of the composites was enhanced with addition of ZnO with increased filler loading. The performance of tensile strength and elongation at break for treated and untreated ZnO-filled UHMWPE were found to decrease with increasing filler loading compared to pure UHMWPE. Both treated and untreated ZnO-filled UHMWPE showed active inhibition towards E. coli (Gram-negative bacteria) whereas slight inhibition for S. aureus (Gram-positive bacteria) from the test. Treated ZnO-filled UHMWPE showed better inhibition against bacteria.