The widespread use of three-dimensional (3D) printing technologies in medicine has contributed to the increased demand for 3D printing materials. In addition, new printing materials that are appearing in the industry do not provide a detailed material characterization. In this paper, we present the synthesis and characterization of polycaprolactone (PCL) based medical-grade thermoplastic polyurethanes, which are suitable for forming in a filament that is dedicated to Fused Deposition Modeling 3D (FDM 3D)printers. For this purpose, we synthesized polyurethane that is based on PCL and 1,6-hexamethylene diisocyanate (HDI) with a different isocyanate index NCO:OH (0.9:1, 1.1:1). Particular characteristics of synthesized materials included, structural properties (FTIR, Raman), thermal (differential scanning calorimetry (DSC), thermogravimetric analysis (TGA)), mechanical and surfaces (contact angle) properties. Moreover, pre-biological tests in vitro and degradation studies were also performed. On the basis of the conducted tests, a material with more desirable properties S-TPU(PCL)0.9 was selected and the optimization of filament forming via melt-extrusion process was described. The initial biological test showed the biocompatibility of synthesized S-TPU(PCL)0.9 with respect to C2C12 cells. It was noticed that the process of thermoplastic polyurethanes (TPU) filaments forming by extrusion was significantly influenced by the appropriate ratio between the temperature profile, rotation speed, and dosage ratio.

In the presented work, for the first time, the metal-modified defective titanium(IV) oxide nanoparticles with well-defined titanium vacancies, was successfully obtained. Introducing platinum and copper nanoparticles (NPs) as surface modifiers of defective d-TiO2 significantly increased the photocatalytic activity in both UV-Vis and Vis light ranges. Moreover, metal NPs deposition on the magnetic core allowed for the effective separation and reuse of the nanometer-sized photocatalyst from the suspension after the treatment process. The obtained Fe3O4@SiO2/d-TiO2-Pt/Cu photocatalysts were characterized by X-ray diffractometry (XRD) and specific surface area (BET) measurements, UV-Vis diffuse reflectance spectroscopy (DR-UV/Vis), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). Further, the mechanism of phenol degradation and the role of four oxidative species (h+, e−, •OH, and •O2−) in the studied photocatalytic process were investigated.

Hybrid materials of conjugated polymer and titanium(IV) oxide have attracted considerable attention concerning their potential benefits, including (i) efficient exploitation of visible light, (ii) a high adsorption capacity for organic contaminants, (iii) and effective charge carriers separation. The new class of the photocatalysts is promising for the removal of environmental pollutants in both aqueous and gaseous phases. For the first time, in this study, the polyaniline (PANI)–TiO2 hybrid composite was used for the degradation of phenol in water and toluene in the gas phase. Polyaniline–TiO2 was prepared by the in situ polymerization of aniline on the TiO2 surface. The obtained hybrid material was characterized by diffuse reflectance spectroscopy (DR/UV-Vis), X-ray diffraction (XRD), fast-Fourier transformation spectroscopy (FTIR), photoluminescence (PL) spectroscopy, microscopy analysis (SEM/TEM), and thermogravimetric analysis (TGA). An insight into the mechanism was shown based on the photodegradation analysis of charge carrier scavengers. Polyaniline is an efficient TiO2 photosensitizer for photodegradation in visible light (λ > 420 nm). The trapping experiments revealed that mainly h+ and ˙OH were the reactive oxygen species that were responsible for phenol degradation. Furthermore, the PANI–TiO2 hybrid nanocomposite was used in gypsum plaster to study the self-cleaning properties of the obtained building material. The effect of PANI–TiO2 content on the hydrophilic/hydrophobic properties and crystallographic structure of gypsum was studied. The obtained PANI–TiO2-modified gypsum plaster had improved photocatalytic activity in the reaction of toluene degradation under Vis light.

In the present study, a novel Fe-ZnO/citric acid-modified cellulose composite (x%Fe-ZnO-y%CAC) was synthesized using an environmentally friendly hydrothermal method. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV−vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectroscopy (FTIR), nitrogen physisorption, and electrochemical and photocurrent density analyses. The influence of the additives from the series of x%Fe-ZnO-y%CAC photocatalysts with Fe content from 0 to 5% and CAC content from 0 to 80% on photocatalytic degradation of ibuprofen (IBU) under simulated solar light was investigated. The photocatalyst 0.5%Fe-ZnO-40%CAC showed high photocatalytic activity of 0.0632 min−1 first-order kinetic rate constant and 46% TOC reduction of IBU under simulated solar light irradiation. Additionally, H2O2-assisted photocatalytic process was investigated for facilitating the IBU degradation in the presence of 0.5%Fe-ZnO-40%CAC; the first-order kinetic rate constant was 2.7 times higher compared to the process without addition of H2O2. Moreover, the effect of radical scavengers was examined to explain the degradation mechanism of IBU by synthesized photocatalysts supported with H2O2. The demonstrated system provides a low-cost and green approach to improve the photocatalytic activity of x%Fe-ZnO-y%CAC photocatalysts.

Hybrid materials of conjugated polymer and titanium(IV) oxide have attracted considerable attention concerning potential benefits, including (i) efficient exploitation of visible light, (ii) high adsorption capacity for organic contaminants, (iii) effective charge carriers separation. The new class of the photocatalysts is promising for the removal of environmental pollutants in both aqueous and gaseous phases. For the first time, in this study, the PANI/TiO2 hybrid composite was used for the degradation of phenol in water and toluene in the gas phase. Polyaniline-TiO2 was prepared by in-situ polymerization of aniline on the TiO2 surface. The obtained hybrid material was characterized by diffuse reflectance spectroscopy (DR/UV-Vis), X-ray diffraction (XRD), fast-Fourier transformation spectroscopy (FTIR), photoluminescence (PL) spectroscopy, microscopy analysis (SEM/TEM) and thermogravimetric analysis (TGA). An insight into the mechanism was shown based on the photodegradation analysis of charge carriers scavengers. Polyaniline is an efficient TiO2 photosensitizer for photodegradation in visible light (λ> 420 nm). The trapping experiments revealed that mainly h+ and ˙OH were reactive oxygen species responsible for phenol degradation. Furthermore, the PANI-TiO2 hybrid nanocomposite was used in gypsum plaster to study the self-cleaning properties of the obtained building material. The effect of PANI-TiO2 content on hydrophilic/hydrophobic properties and crystallographic structure of gypsum was studied. The obtained PANI-TiO2 modified gypsum plaster had improved photocatalytic activity in the reaction of toluene degradation under Vis light.