Macroscopic preparation of polylactic acid/graphene composite fiber film with efficient antibacterial and thermal properties

Photothermal antibacterial composite membranes have a broad range of clinical applications such as wound dressing, drug delivery, and physiotherapy. However, existing photothermal antimicrobial films have limitations related to biosafety, stability, and degradability. Herein, we develop an environmentally-friendly composite membrane with antibacterial properties, photothermal conversion capability, and facile processing. The composite membrane film is comprised of polylactic acid (PLA) with graphene (G) and is synthesized via melt co-blending and hot pressing. We verify that graphene is uniformly dispersed in the PLA phase, and an antibacterial rate of 99.7% can be achieved by a PLA/G composite membrane with only 3.0 wt.% graphene added. Moreover, the obtained films exhibit efficient photothermal conversion, reaching thermal treatment temperatures (40-60 degrees C) within 10 s and maintaining temperature stability for extended periods. Additionally, the composite fiber film exhibited a tensile strength of 3.5 cN/dtex and good hydrophobicity (>90 degrees contact angle). The combination of antibacterial properties, efficient photothermal conversion, noninfiltration, high strength, hydrophobicity, and mechanical stability, along with the inherent degradability of PLA and the scalability of the synthesis process for mass production, offer broad application prospects for PLA-based composite materials.