Physiological and Biodegradation Changes Properties of PLA\UHMWPE\PVA Blends During Early Stage of Biodegradation in Vivo

Biodegradable plastic blends from natural sources, namely pure polylactic acid (PLA) and polyvinyl alcohol (PVA) with ultra-high molecular weight polyethylene (UHMWPE) softener, were studied to investigate changes in their physical properties resulting from in vivo biodegradation at body temperature. These blends are also suitable for the manufacture of medical scaffolds and artificial joints. Fourier transform infrared (FTIR) spectroscopy revealed a significant change in the chemical composition, manifested by improved cohesion and structural diffusion. Furthermore, a broad band appeared in the 3417–3471 cm-1 region, representing a clear modification of the spectra and leading to the formation of a biofilm on the outer surface of the samples. DSC analysis supported the clear effect across all blend spectra. Changes in the gravimetric values confirmed that the PVA\PLA/UHMWPE samples degraded significantly faster with increasing PVA volume fraction, and PVA completely disappeared at higher volume fractions. It was also shown that PLA did not degrade rapidly into PLA/UHMWPE in vivo, maintaining its overall structure and weight unchanged.