New synthetic Ni-talc was used as filler in the synthesis of polyurethane (PU) nanocomposites by in situ polymerization and to emphasize the contribution of the new material compared with natural talc. Good dispersion of Ni-talc was supported by homogeneous green coloration observed in the polymer matrix. X-ray diffraction (XRD) analyses indicate the intercalation of polymeric matrix into the filler layers by the increase in d 001 -spacing value of the Ni-talc for the nanocomposites when compared to the pristine filler. The nanocomposites obtained with synthetic talc showed an improvement in the crystallization temperature and in thermal stability when compared to pure PU and the composite obtained with natural talc. The young modulus of PU/talc materials containing both Ni-talc and natural talc were slight higher than pure PU. As shown by scanning electron microscope (SEM), Ni-talc fillers were well dispersed into the polymeric matrix probably due to the good compatibility of both phases filler/polymer mainly achieved by the filler OH interaction with the urethane group of the polymeric chain.

This work presents the syntheses of PU nanocomposites, by in situ polymerization technique, using different synthetic talcs as inorganic filler. The fillers were obtained from two different hydrothermal treatments and composition (talc-Mg and talc-Ni). For nanocomposites syntheses 3% w/w of synthetic talc were added related to the weight of pure polymer. Samples were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) to understand the influence of the fillers syntheses and composition in morphological and thermal properties of the obtained nanocomposites. When talc-Ni was used as filler, the resulting nanocomposite was intercalated while with talc-Mg was exfoliated into the polyurethane matrix. Both fillers have increased the thermal properties of the polymer, but the exfoliated nanocomposite provided higher thermal stability.

Two new synthetic silico-metallic mineral particles like TOT-TOT swelling interstratified (SSMMP) produced with distinct hydrothermal processes (talc 7 h/315°C and talc 24 h/205°C) were used to synthesize polyurethane nanocomposites by in situ polymerization technique. These fillers were added in a range of 0.5-5 wt% related to the mass of the pure polymer. The dispersion and interaction between the fillers and the polymeric matrix were evaluated by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The X-ray analysis indicated that the synthetic SSMMP are well dispersed/or exfoliated into the polymer matrix. The high surface area of the synthetic SSMMP was significant for the increase in the crystallinity and thermal properties of the nanocomposites. In the case of Young's modulus, for nanocomposites PU/SSMMP 24 h and the pristine PU, a similar behavior was observed. However, for the nanocomposites PU/SSMMP 7 h, an increase in the Younǵs modulus values until 3 % of filler addition when compared to pure PU was noticed. The creep-recovery test showed that both SSMMP behave as a mechanical restraint of the polyurethane chains. The results evidenced the importance of the SSMMP syntheses conditions to obtain nanocomposites with desired properties.

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Optically transparent membranes from bacterial cellulose (BC)/polycaprolactone (PCL) have been prepared by impregnation of PCL acetone solution into dried BC membranes. UV-Vis measurements showed an increase on transparency in BC/PCL membrane when compared with pristine BC. The good transparency of the BC/PCL can be related to the presence of BC nanofibers associated with deposit of PCL nano-sized spherulites which are smaller than the wavelength of visible light and practically free of light scattering. XRD results show that cellulose type I structure is preserved inside the BC/PCL membrane, while the mechanical properties suggested indicated that PCL acts as a plasticizer for the BC membrane. The novel BC/PCL membrane could be used for preparation of fully biocompatible flexible display and biodegradable food packaging.

Titanium has been widely used as biomaterial, especially in implantables, in which osseointegration and corrosion resistance are needed. Studies have shown that the thickness and roughness of porous titanium oxides are related to the osseointegration. According to the literature, the best anodizing conditions for obtaining nanotubes in titanium oxide are the use of a voltage of 10V in an electrolyte containing 0.15% HF in H3PO4 (w/v). In this study, was to evaluate the corrosion capacity of simulated body fluid (SBF) over titanium samples anodized on 1 mol. L-1 H3PO4 and 0.15% HF (w/v) in 1 mol.L-1 H3PO4. To perform these evaluations samples of commercially pure titanium grade 2 were used. Samples were analyzed by scanning electron microscopy, atomic force microscopy and by electrochemical corrosion tests in healthy and simulating inflammatory conditions. The hydrophobicity of oxides was tested by sessile drop essay, also using SBF. Results show that oxides obtained in H3PO4 electrolyte, barrier type oxides, work better than the porous oxides obtained in H3PO4/HF electrolyte, suggesting that barrier oxide exhibit more biomaterial characteristics than the porous oxide. These results agree with previous studies, and stand out mainly in relation to the tests performed under inflammatory conditions, more aggressive to the biomaterial.

In many places, charcoal production, using Australian Blackwood, is still a rudimentary process, generating huge environmental impact, due to the release of pyrolysis smoke into the atmosphere. Both the society and governmental agencies is pushing the factories to condense the smoke, generating byproduct known as pyroligneous liquor. Although it's largely used for agricultural purpose, as a fertilizer and phytosanitizer, its chemical composition presents hydrogen and oxygen rich compounds, making it a potential electrolyte in the surface treatment industry, especially for anodization. Organic alternatives are being used to replace these electrolytes to make the anodizing process cleaner. Then, for the first time, Australian Blackwood pyroligneous liquor was used as an anodizing electrolyte for titanium TICP-G2, to obtain oxides for protection and coloring of the metal. For such, suitable parameters to execute the process were determined (dilution, current density, temperature, agitation, pH, conductivity) and an analysis of the transient potential over time was made. The anodized surfaces were characterized using top view Scan Electronic Microscopy (SEM) and Grazing Incidence X-ray Diffraction (GIXRD). Based on the results presented, it can be concluded that the best parameters to anodize the titanium were obtained with 50% pyroligneous liquor diluted in water, obtaining colored surfaces and promoting the formation of oxide crystallites clusters mainly in longer process times (3600s).

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