Investigation of PP monofilament structural changes with various conditions used for deposition of TiO2 atomic layers by ALD technique

Atomic layer deposition (ALD) technology makes it possible to obtain biocompatible and homogeneous ultrathin oxide layers, which creates opportunities to modify the surface properties of PP surgical meshes, for example, through TiO2 deposition. The aim of this study was to investigate the changes occurring in the structural and physical properties of polypropylene (PP) monofilaments used for surgical mesh production after deposition of a thin film of titanium oxide by the ALD method under various conditions. The titanium oxide was deposited from TiCl4 and water in the temperature range 100 °C–160 °C. The surface morphologies and chemical compositions of the deposited layers were studied with scanning electron microscopy (SEM) with energy-dispersive X-ray chemical microanalysis (EDS). Structural investigations of the PP monofilaments were carried out with wide-angle X-ray diffraction (WAXD) and Fourier transform infrared spectroscopy. The thermal properties of the PP monofilament were characterized with differential scanning calorimetry (DSC). Additionally, the effects of structural changes were evaluated with tensile strength tests. The results made indicated the critical thermal conditions required for TiO2 deposition on PP substrates with the ALD method. •ALD can be successfully used for the TiO2 deposition on temperature-reactive materials as polymers e.g. PP.•The stable range of temperature during ALD surface modification of polypropylene is 100–130 °C.•Thermal crystallization above 150 °C resulted in supramolecular structural changes and created a small amount of the γ form.•On the basis of the conducted research, the optimal ALD deposition temperature of TiO2 on polypropylene was 120 °C.