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This work includes the search for the development of a composite of a WPU (waterborne polyurethane), β-CD (β-Cyclodextrin), PZnO (zinc oxide particles), and the presence of CaCO3, to obtain new properties such as adhesion to multiple substrates of organic and inorganic origin. Therefore, a development sequence was proposed: Computational development: conformation of the polymeric matrix (with the intermediary polymers) and simulation of the interaction between β-CD and PZnO and Ca+2 and CO3-2 ions, as well as insertions in β-CD, computational simulations were carried out with the help of ACD LABS™ (free version) software and by molecular dynamics with GROMACS™. With the above, we were able to determine properties such as interfacial tensions, surface tensions, and contact angles, and degrees of solvation and stability in waterborne emulsions. Therefore, it is important to point out that one of the main contributions of this research proposal is that there are no studies that combine these materials.

Magnetic nanoparticles have been used to confer better properties to materials, particularly to polymers. Due the properties of the polymer, such as flexibility and lightness, combined, white nanoparticles provide other properties such as microhardness, corrosion resistance, among others. In this study, three types of nanoparticles were elaborated: magnetite, cobalt ferrite and nickel ferrite, through the coprecipitation method used in the elaboration of skin-like polyurethane (PU) -based composites. Specimens were made at different nanoparticle weights (0.1%, 0.3%, 0.5% and 1.0%). Likewise, the hardness was measured by means of a phase II Model PHT-2500 portable digital hardness tester and the tension tests were carried out on an Autograph Shimadzu universal machine. The stress results were plotted using the Jupyter Notebook for interpretation. Finding some improvements in the materials manufactured using the different ferrites already mentioned.

The creation of films formed by the incorporation of ZnO or TiO2 in poly(methylmethacrylate) PMMA matrices was proposed in order to improve their properties as resistance to high temperatures. ZnO and TiO2 nanoparticles were synthesized by the sol-gel method, which does not require the use of surfactants and is easily scalable. In the present work, zinc oxide (ZnO) or titanium oxide (TiO2) incorporations were carried out in a polymeric matrix of Poly(methylmethacrylate) PMMA. Both oxides were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD) and diffuse reflectance UV-Vis spectroscopy. PMMA was obtained by the suspension free radical polymerization method and PMMA composites containing ZnO or TiO2 were obtained. Polymer characterization was performed using Fourier transform infrared spectroscopy (FTIR). The composites were analyzed by thermogravimetric analysis (TGA) and its thermal resistance was found to be the best incorporation of TiO2 in 1%.

Due to continuous use and environmental factors (humidity and continuous exposure to the sun), the leather upholstery experiences cracking, discoloration and possible yellowing. The above factors significantly decrease the life of leather upholstery in cars. The objective of this work is to synthesize zinc oxide nanoparticles, which have optical properties that allow it to absorb UV radiation and then incorporate them into a polymeric matrix to develop a coating with UV protection for leather finishing in the automobile industry. The particles of zinc oxide were synthesized by the sol-gel method to obtain a nanometric particle size, the method represent a low-cost synthesis method, without the use of surfactants and easily scalable. With monoethylene glycol was formed a stable colloid with the zinc oxide nanoparticles and the polymer matrix. Finally, the final leather finishing obtained for the automotive industry has greater resistance to bending, also thermal stability was improved. In consequence, the lifetime of the leather finishing has improved.

The objective of the present article is to introduce nanoparticles of a ferromagnetic material (magnetite) to the polymer matrix. We will make some study to verify that the coupling of the nanoparticles in the material was carried out. The present work describes the self-assembly of nanocomposite in suspensión polymerization of PS/PMMA block copolymer, containing magnetite (Fe3O4) which is sonicated with the monomer mixture, with percentages of 0.25% and 0.5% in proportion of the weight of mixture. Photographs were taken with the microscope to verify the coupling of the ferromagnetic material to the polymer matrix, and to verify that couplig, we made characterization by infrared spectroscopy. Also describes the process of nanocomposite synthesis using co-precipitation method, in which ferric chloride and ferrous chloride are combined in an excess basic medium, to subsequently induce the precipitation of the material with a magnet.

The creation of films constituted by semiconductor oxides of zinc oxide (ZnO) incorporated into a polar polymer matrix was proposed, looking for such films to be easy to apply, friendly to the environment and compatible with materials. Within the experimental process, the synthesis of styrene copolymers with a polar monomer (methyl methacrylate) was carried out through the suspension and emulsion polymerization processes.

Currently, the polymers industry has gained increasing importance due to the versatility of its properties. In this work were synthesized copolymers of styrene with vinyl acetate at different concentrations through a process polymerization of suspension, which are the starting points for obtaining of composites with polyaniline synthesized PANI chemical oxidative polymerization process, used for doping HCl at a concentration of 1.5 M and ammonium persulfate 0.5 M in a mass radio of 1:1. The conductivity was evaluated by means of cyclic voltammetry and impedance spectroscopy, in order to determine the effect of the concentration of the polar monomer in the composite founded that increase concentration of polar comonomer the conductivity also too.

In this work, electrochemical sensors were developed for the detection of artificial sweeteners such as D-sorbitol and Maltitol in aqueous solutions. These compounds are classified as polyalcohols and are widely used in the food and beverage industry to replace common sugar. However, their consumption is not currently regulated, and excessive use leads to consequences in the body such as increased blood glucose levels. Graphene oxide (OG) inks were prepared, which were deposited on vitreous carbon (CV) electrodes, followed by enzymatic immobilization. The detection capacity of the biosensors was evaluated applying electrochemical techniques. The biosensor with the best levels of detection, reproducibility and durability for the analytes under study for the detection of D-Sorbitol turned out to be that measured at a working voltage of 0.86 V vs Ag / AgCl / KCl (3 M), depositing 20 μL of OG ink and using a dilution of 0.5 μL / 100 μL of (alcohol oxidase / PBS). In the case of Maltitol the best designed biosensor was worked at 1.06 V vs Ag / AgCl / KCl (3 M), depositing 20 μL of OG ink and using a dilution of 2.0 μL / 100 μL of (alcohol oxidase / phosphate buffer).

Objectives. The electrical impedance spectroscopy (EIS) is relatively new technique used in medicine. The main problems that should be solved are its low resolution and that it fails to distinguish between tissue types, so some kind of the contrast should be applied. Magnetical nanoparticles have been used for imaging and other medical applications. For that reason, our research group decided to analyse the changes of electrical properties of chicken muscle tissue caused by three different types of metal nanoparticles at 50KHz. Methodology. Bio-Logic Science Instruments SP-150 was used as EIS device. Three different particles were analysed: two types of nanomagnetite (NM1 and NM2) and one of Gold particles (GNP). NM1 and NM2 samples were synthetized by coprecipitation and combustion method, respectively. GNP were synthetized by Turkevich method. Nanoparticles were characterized by SEM and RAMAN spectroscopy. Four needles were placed in each chicken breast to connect the EIS device. Measurements were obtained from each chicken breast at basal stage and after being injected with nanoparticles. Data was analyzed by bode graphics (module and phase). Contribution. The major changes of electrical properties of tissue were evidenced by using NM1 and GNP.

Objectives. Contamination with heavy metals has augmented in last decades due to several factors. So, scientific community has a challenge to develop new and more efficient methods for contaminants removal. Electroadsorption is one of investigated techniques with promising results. The main challenge with this technique is determination of optimal parameters, such as electrode material, time and conditions of adsorption. Material for electrode for electroadsorption must fulfil some criteria: high electroactive area, low electrical resistance and environmental compatibility. For that reason, our research group decided to synthetize a set of new carbon materials with high surface area and features than make them interesting to test them as an electrode material. Methodology. 3 carbon materials were synthetized by sol-gel method using different time and temperature conditions. All materials were characterized by scanning electron microscopy and other techniques. FTO glasses were modified with synthetized materials separately. Electroadsorption of Cu (II) was conducted at room temperature. Contribution. In this work we demonstrate an easy synthesis of 3 carbonaceous materials with high surface area capable to remove Cu (II) from water solution by electroadsorption.

Objectives. Electrical impedance spectroscopy (EIS) is a harmless non-invasive technique that allows to measure and monitor different physiological parameters. One of the problems with establishing new procedures based on EIS is difficulty to distinguish between tissue types. For that reason, our research group have decided to assess a possibility to use nanomagnetite as a contrast medium in EIS procedures. In this work we present characterization the electrical properties of a porcine heart tissue by EIS using a magnetite particles suspension as contrast medium. Methodology. SP-150 from BioLogic Science Instruments was used as EIS equipment. Porcine heart tissue was used as biological tissue. Nanomagnetite particles were synthetized by coprecipitation and combustion methods and named NM1 and NM2, respectively. EIS device was connected at each ventricle through four hypodermic needles (38mm). Left and right ventricle was injected with NM1 and NM2 particles, respectively. Impedance measurements were acquired for each ventricle before and after the injection. Contribution. Both samples of magnetite nanoparticles were able to change electrical properties of heart tissue. Studies in vivo must be performed in order to confirm the conclusion.