Controllable degradation rates, antibacterial, free-standing and highly transparent films based on polylactic acid and chitosan

Plastic wastes have brought increasingly serious environmental white pollution, further boosting the research of degradable materials. Here, the free-standing degradable film based on polylactic acid(PLA)/chitosan(CS) was fabricated by non-solvent induce phase separation method. The optical and scanning electron microscope images, FTIR spectra, transmittance, water contact angle, thermal gravity analysis, differential scanning calorimetry, degradation rates and antibacterial activity were tested. The prepared film had porous structure and highly transparent capability. And the hydrophilicity of composites was improved while the thermal stability was slightly reduced. Besides the degradation rates could be tuned in terms of structures through changing pore sizes of PLA-based films. Moreover, the film showed strong antibacterial activity against E. coli. The free-standing and highly transparent degradable films have great potential applications in biomedical fileds and food packaging areas.