Infrared analysis of plasma polymerized hexamethyldisiloxane for biocompatible composites

There is an increasing interest in utilizing polymers as matrices for calcium phosphate based composites used in hard tissue implants. Plasma polymerization gives a possibility for obtaining polymers with different compositions and structures from simple monomer molecules, by varying the polymerization conditions. The structure of plasma polymer layers obtained from hexamethyldisiloxane (PPHMDS) was studied by infrared spectroscopy. The analysis of the obtained plasma polymers indicates a long chain polysiloxane structure resulting from the removal of some methyl groups from the monomer molecule. The influence of the plasma polymerization conditions - the monomer flow rate and the current density of the glow discharge on the chemical structure, was studied. The effect of the silica glass substrate on the polymer structure was established. The growth of the hydroxyapatite (HA) layer from a suspension of saturated simulated body fluid (SBF) and detonation nanodiamond (DND) on the polymer film was carried out, and the structure of the obtained layers was investigated. The results emphasize the possibility for tailoring the polymer structure by varying the deposition conditions and the substrate, in order to use them in biocompatible materials.