Polylactic Acid Thin Films Properties after Steam Sterilization

This paper presents data on the effects of steam sterilization on the properties of thin films based on polylactic acid. It has been established that thin films based on polylactic acid and poured from solutions of 10, 20, and 30 g have two topographically different sides. One side (internal) has a more prominent surface. The other side (external) has a smooth surface. It is reflected in the roughness parameters. R a of the internal side varies from 0.01 to 0.018 μm. R a of the external side is 0.17–0.4 μm. The average roughness increases from 0.17 to 0.4 μm with an increase in the mass of the solution poured into films. Sterilization contributes to a change in the surface of the polylactic acid films and makes their profile more prominent. This leads to a significant increase in the roughness of both sides by more than 5 times. In addition, it was found that thin polylactic acid films have hydrophobic (θ = 80°) properties. Steam sterilization reduces the wetting angle by 14°–15° (17–18%) and increases the surface energy values to a greater extent owing to the polar component. These changes increase the hydrophilicity of the studied material.