Preparation and antibacterial properties of polypropylene composite with bisphenol A-type benzoxazine.

Polypropylene (PP) is a commonly used material in medical supplies. However, its lack of antibacterial properties has led to a frequent occurrence of healthcare-associated infections that need to be addressed. This study extensively investigates the antibacterial effects of bisphenol A-type benzoxazine (BA-a), revealing a relationship between the curing degree of BA-a and its antibacterial performance. A lower degree of curing corresponds to stronger antibacterial activity. At the processing temperature of 170 °C, the curing degree of BA-a reached only 14.6%, and it had strong antibacterial activity. Based on this relationship, a melt blending method at 170 °C is determined to prepare PP/BA-a composite material, aiming to enhance the antibacterial properties. The antibacterial performance of PP/BA-a is evaluated by plate coating method. The results demonstrate that PP/0.8BA-a exhibits an antibacterial rate as high as 99.99% against E. coli and S. aureus. Migration experiments confirm the stability of the antibacterial effect. The extracts from PP/BA-a show no toxicity towards mouse fibroblast cells (L929). Furthermore, compared to pure PP, the addition of BA-a improves the thermal stability of PP/BA-a, with an increase of 56 °C in the onset thermal decomposition temperature (T5%), enabling PP to better adapt to the high-temperature environment of moist heat sterilization. This study presents a novel method for obtaining highly antibacterial medical polymer materials (PP/BA-a) with broad application prospects. [ABSTRACT FROM AUTHOR]