Antimicrobial Modification of PET by Insertion of Menthoxy-Triazine

Microbial contamination on polyethylene terephthalate (PET) negatively affects human health. Thus, there is still a challenge endowing PET with nonleaching antimicrobial performance. Here, menthoxytriazine was inserted into the backbone of PET, named PEMT, through polycondensation between ethylene glycol (EG) with 2-menthol-4,6-aminobenzoic-1,3,5-triazine (DPMT). The antimicrobial adhesion performances of PEMT were evaluated by antibacterial adhesion test and antifungal landing test. The antibacterial adhesion test indicated that the PEMT possessed better antibacterial adhesion capability than raw PET, achieving 93.3% and 88.3% resistance against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive). An antifungal landing test exhibited that PEMT had better resistance to Aspergillus niger (fungi) contamination compared to PET. Zone of inhibition, water contact angle, and BacLight live/dead fluorescent experiments were used for a deeper analysis, illustrating that the stereochemical structure of menthoxy group played a key role in the antimicrobial adhesion mechanism. In addition, the results of MTT assay illustrated the PEMT was a noncytotoxic material. This work presents an effective strategy for the antimicrobial adhesion modification of PET.