Titanium alloy surface coatings using poly(sodium styrene sulfonate) and poly(acrylic acid)

Osseointegration of implant materials with surrounding tissues is crucial for their long-term success.

The aim of the present study was to investigate the extent of physisorption of polymers on a titanium alloy (Ti6Al4V) surface. In addition, the water contact angles on the physisorbed coatings were measured to compare the hydrophilicity of the modified surfaces.

Ti6Al4V disks (13-mm diameter) were prepared to evaluate polymer adsorption on the alloy surface. The surface hydrophilicity was evaluated by contact angle (Θ) measurement. Physisorption of polymers on the surface was evaluated quantitatively by a colorimetric method.

The largest contact angles were recorded on samples polished with silicon carbide papers of 1200 and 500 grit (Poli1200 and Poli500 samples: 97.3 ± 4.8 and 84.8 ± 11.0, respectively). Treatment of polished samples with Kroll solution remarkable reduced the contact angles to 46.8 ± 11.6 and 58.6 ± 11.5 for Poli500+Kroll and Poli1200+Kroll, respectively. Contact angles were further reduced in response to PolyNaSS and PAA treatment. Regardless of surface treatment, there was no significant difference in the contact angles on surfaces after SiC 500 and 1200 grit polishing.

Physisorbed polymer coatings (such as PAA) on the Ti6Al4V surface can reduce the contact angle and improve the hydrophilicity and wettability of the alloy surface. Moreover, physisorption is a simple technique that does not require any special equipment.