Forming of polypropylene film with the addition of dibutyrylchitin and stearic acid

In this work, polypropylene (PP) films with varying percentages of dibutyrylchitin (DBC) and stearic acid (SA) were prepared. In the first stage, the PP film was treated with diisopropyl ether to extract stearic acid, resulting in a porous structure of the PP film containing the DBC additive. Only stearic acid was washed out, as the diisopropyl ether is not a DBC solvent. In the next stage, the film was treated with a 5% potassium hydroxide solution to convert DBC into chitin and to convert any remaining SA into potassium stearate (SP). Washing out the resulting SP with distilled water yielded porous PP film with chitin and its derivative of DBC. Chemical changes occurring during processing were examined using Fourier Transform Infrared Spectroscopy (FTIR). The morphology of the film surface at consecutive processing stages was imaged using microscopic methods: scanning electron microscopy (SEM) and optical microscopy (OM). After solidification of the PP polymer matrix, the applied SA crystallises on the surface of the PP film. As a result of the applied procedure, the PP film with the addition of DBC and chitin was obtained. It is anticipated that this bioactive material can be used in medicine, e.g., as a wound dressing, hernia mesh, or scaffolds.