This project studies the alternative chemical recycling of disposable bottles as raw material for the manufacture of a product known as polymeric concrete, which has several applications in the construction industry. Crosslinked materials from polyethylene terephthalate (PET), glycerol and clay were obtained. First recycled PET bottles were washed, cut and dried; after bis-hydroxyethyl terephthalate monomer was obtained from depolimerization reaction of PET. The monomer, glycerol and titanium dioxide reacts to synthesize a polymeric concrete. Materials with concentrations of clay from 1, 10, 20, 30, 40 and 50%w/w were obtained. Differential scanning calorimeter (DSC), Soxhlet extraction, colorimetry and Shore D hardness were used to characterize the materials. The results indicated a degree of crosslinking in the synthesized material when the amount of clay was increased. A melting point around 265 °C was not observed by DSC analysis; this suggests that a crosslinked material was formed. By TGA analysis temperature degradation was observed at 394°C, which it was increasing from 408 to 416°C according to the addition of clay content. A bad dispersion of particles in the crosslinked polymer decreased the thermal stability of PET when the clay content was increased.

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Biosurfactants are metabolites produced by microorganisms during their growth and reproduction. They are amphiphilic molecules capable of modifying surface and interfacial tension. A petrophilic, nitrogen-fixing, phosphorus-solubilizing, and biosurfactant-producing bacterial strain was isolated and characterized. The isolated strain was cultivated in Kim medium with a C:N ratio of 2:1, from which its growth kinetics was determined. Samples of the culture broth were taken at different times and the collapsed drop, oil dispersion and emulsification index tests were performed. Maximum culture growth occurred at 72 h. The biosurfactant was extracted from the crude cell-free broth using a mixture of solvents and a yield of 2.21 g/L was obtained. Thin-layer chromatography and FT-IR analyzes revealed the presence of a lipopeptide biosurfactant. Tensiometry tests showed that the biosurfactant was able to lower the surface tension of water from 72 mN/m to 40 mN/m and the critical micelle concentration was 0.058 (w/w). Probit analysis for toxicity determination showed that there was no weight loss in Eisenia foetida specimens in a range between 10000 and 50000 ppm.

The present project explains how crude biodiesel (crude BD) has been obtained by using coconut oil and ethyl alcohol as well as sodium hydroxide as a catalyst. The coconut oil was extracted with water which was submitted to evaporation afterwards. This experiment was carried out by adding the coconut oil in a 500 mL glass flask. The catalyst was dissolved in ethyl alcohol and mixed together with the coconut oil. Once obtained the mixture, this was stirred for 25 minutes at temperatures from 20, 30, 40, 50 to 60 °C. During the reaction, two phases were formed: crude biodiesel (top layer) and crude glycerol (bottom layer). The characterization was done by determination of pH (using an electrode located in the top layer connected to a computer by RS-232 interface system). When the separation concluded, the crude BD was rinsed in order to remove the catalyst. The characterization of washed biodiesel was determined by density and Saybolt viscosity. Fourier Transform Infrared (FTIR) analysis was also made. The results by FTIR indicated the two functional groups of fatty acid ethyl esters (C=O, 1733 cm-1 and C-O, 1154 cm-1) and the OH wide band group of glycerol at 3400 cm-1. When the reaction time ended, the maximum pH value registered was 12.7. The values for pH, density and Saybolt viscosity were acceptable for crude BD and crude glycerol.

This work is about the production of hybrid coatings of the system SiO2-PMMA (PMMA, polymethylmethacrylate). These materials have interesting mechanical and chemical properties useful for anticorrosive and wear resistance applications. SiO2-PMMA hybrids were obtained by the sol-gel traditional process, using tetraethylorthosilicate (TEOS) and methylmethacrylate (MMA) by Aldrich Co, as starting reagents. The SiO2:PMMA ratio was varied from 0:1 to about 1:1 at air atmosphere deposition. The coatings were obtained on acrylic sheets and silicon wafers. A diversity of coatings with chemical composition ranging from SiO2 and PMMA to obtain the SiO2-PMMA hybrids were obtained. Infrared (IR) and atomic force microscopy (AFM), were performed to determinate structural and morphological behavior.