Effect of Heating on Antimicrobial Properties in Bamboo Powder／HDPE Composite

We investigated the development of composite materials endowed with antimicrobial properties with a view using natural materials to reduce the amount of plastic in use. In this study, we focused on bamboo powder, which has long been known as a natural material endowed with antimicrobial properties. We tested the antimicrobial properties of heat-treated bamboo powder to obtain its antimicrobial spectrum. Next, we estimated the antimicrobial properties of high-density polyethylene (HDPE) with 50 wt％ heat-treated bamboo powder composites. As a result, we clarified the antimicrobial properties in respect to Staphylococcus aureus in bamboo powder by heating at appropriate temperatures. We also confirmed the antimicrobial properties of bamboo powder in respect to Bacillus subtilis, Moraxella osloensis, and Escherichia coli. Furthermore, we found that the bamboo powder/HDPE composite could be endowed with antimicrobial properties without heating the bamboo powder in advance by increasing temperature in the molding processing. These results imply that the antimicrobial properties of bamboo powder/HDPE composite can be controlled by selecting the processing temperature.