Influence of Fillers on Mechanical Properties of Medical-Purpose Siloxane Films

The preliminary results of studying the efficiency of using the siloxane low-molecular-weight SKTN-A rubber as a matrix for a thin-film drug coating of implantable stents are presented. A porous film structure is formed by the introduction of intermediate (removable) fillers, such as ethanol, sodium hydrocarbonate, and high-molecular-weight chitosan. The ultimate tensile strength and the relative elongation of the prepared films are studied. The strength of the films formed using ethanol is found to be nearly analogous to that of pure siloxane, but their relative elongation is lower by 10%. The use of sodium hydrocarbonate makes it possible to enhance the strength of the films by 37% (to 0.22 MPa), and the relative elongation increases to 93%. When chitosan is used, the strength of the films increases almost twofold (to 0.28 MPa) and their plasticity is similar to that of pure siloxane and amounts to approximately 40%.