Plasma treatment of the surface of poly(hydroxybutyrate) foil and non-woven fabric and assessment of the biological properties

This paper deals with the poly(hydroxybutyrate) (PHB, foil and fabric) surface modification, characterization and the view of its possible application. The influence of Ar plasma treatment on surface polarity was studied. The changes of the surface parameters were determined immediately after treatment and after annealing related to plasma power, treatment time and heating. These surface-induced differences were studied by different analytic methods: polarity (wettability) was studied by contact angle measurement and surface energy calculation, the surface morphology analysis was done by atomic force microscopy and for determination of chemical composition of surface layer the XPS analysis was used. It was found that after plasma treatment the surface energy of both PHB foil and non-woven fabric significantly increased. PHB non-woven fabric exhibited almost immeasurable contact angle after the plasma treatment. The wettability of both types of PHB substrates after heating was completely inversed. The significant change in roughness of PHB foil was found. After the plasma treatment, the material ablation was determined, which was also connected with surface chemical changes, thus the surface was found to be corrugated. The heating procedure induced “little” crystallites on the surface. Positive effect of PHB foil modifications on surface biocompatibility was confirmed. The biocompatibility was also preserved when thermal stress was applied. Silver nanolayer sputtered on PHB fabric surface induced strong anti-microbial properties.