In this study, a method for preparing bilayer films based on a polyelectrolyte complex of sodium hyaluronate and chitosan is presented, with a view toward biomedical applications. The effects of the component mass ratio, layer deposition sequence, and film thickness on the structure, morphology, and mechanical properties of the resulting films were investigated. Formation of the polyelectrolyte complex was confirmed by FTIR spectroscopy, which revealed characteristic changes in the absorption bands of the polymers’ functional groups. The morphological features of the polymer films were evaluated by optical microscopy, and tensile testing was used to determine their mechanical performance. The optimal film properties were achieved at a hyaluronic acid (HA-Na) to chitosan (CH) mass ratio of 1:7 and a layer deposition sequence of HA-Na → CH. Increasing film thickness by increasing the volume of the deposited layers resulted in a pronounced improvement in tensile strength and elongation at break. Overall, the findings demonstrate that the properties of sodium hyaluronate/chitosan bilayer films can be purposefully tuned by varying processing parameters, making these materials promising biomedical film matrices for the treatment of injuries and tissue damage. 

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