Polyethersulfone (PES) hollow fiber membranes were produced, containing 3% of two types of clay (Brasgel PA-MMT and Cloisite NA-CLNa), in order to modify the characteristics of the polyethersulfone membrane. By means of the X-ray diffraction, it was possible to observe an exfoliated and/or partially exfoliated structure in the membranes containing clay. From the analysis of contact angle, it was possible to notice an increase in the hydrophilicity of the membrane with the introduction of the clay. Through scanning electron microscopy (SEM), the morphology of the porous support of the membrane was modified with addition of clay, favoring greater uniformity of the pores and fingers. In the flow measurements with distilled water, the membranes with clay obtained the highest flows, being the greater flow with the Cloisite Na clay (~22 L/h.m 2) and was in agreement with the contact angle results. In the analysis of permeation with the oily emulsion, the membrane with Brasgel PA clay in its structure presented the greatest flow (~16 L/h.m 2) and the membrane with Cloisite Na presented the greatest yield (78.28%). Therefore, the clay acted by modifying both the morphology and the hydrophilicity of the polyethersulfone membrane, improving flow and yield.

Membranes have been widely used in the treatment of industrial effluents. However, there are still some limitations in the separation and permeability with respect to these effluents. Therefore, this study investigated the addition of 1% and 5% of an inorganic filler (clay) in polyethersulfone polymer membranes. By contact angle analysis, it was observed that the clay influenced the hydrophilicity of the membrane. The presence of the clay had an important role in the morphology of the membrane, modifying and favoring a greater quantity of pores and macropores for the porous support. For the tensile test, it was seen that the high clay content decreased the membranes properties. The flow tests, having a flow stabilized around 300 L/h·m 2 for membranes containing clay, evidenced the efficiency of the membrane for the treatment of indigo blue, representing a 200% increase in relation to polyethersulfone membrane. The membrane containing 1% of clay presented the highest level of rejection to the effluent, around 94.0%. Thus, it was evident that the addition of montmorillonite clay modified the membrane structure contributing to a higher selectivity and permeability.

In this work, polyamide 6 membranes (PA6) and hybrids with 1, 3 and 5% of montmorillonite clay (MMT) were obtained, adding potassium chloride (KCl) and calcium chloride (CaCl2). These different additives are intended to promote formation and increase of the pores in the microporous membranes. The membranes in the form of thin films were prepared by the phase inversion technique, leading to flat selective barriers. The MMT clay was characterized by X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The membranes were characterized by XRD, FTIR, scanning electron microscopy (SEM), contact angle, water vapor permeation, flow measurements and yield. The clay XRD results showed characteristic peaks of bentonite containing accessory materials, as well as a peak at 5.93°, indicating the d001basal interplanar distance of 14.95 Å of MMT. In the spectrum in the infrared region of the clay, it was observed the presence of hydroxyls inherent to the adsorbed water, as well as characteristic bands of Si-O-Si bonds and the octahedral layer of MMT. The viscosities of the solutions of PA6 and their hybrids with CaCl2were higher compared to solutions containing KCl due the CaCl2possess a bivalent ion with a high degree of hydration and a molecular mass higher than KCl. In addition, these salts promote formation of hydroxides that precipitate the particles of MMT, decreasing the viscosities with the increasing percentage of clay. By means of the X-ray diffraction, it was possible to perceive that the hybrid membranes with the inorganic salts suggest an exfoliated and/or partially exfoliated structure. From the results of the FTIR analysis the bands obtained in the PA6 membranes and its hybrids remained practically unchanged, as there was an increase in the clay content and the introduction of the inorganic salts. From the photomicrographs obtained by SEM, it was observed that the addition of clay in the hybrid membranes provided an increase in the number of pores with the gradual increase of the percentage of clay. While the addition of the inorganic salts (KCl and CaCl2) provided an increase in the pore size of the top surfaces of all membranes, by means of the contact angle, it was verified that the hybrid membranes presented smaller angles when compared to the PA6, probably, due to the superficial peculiarity of the clay to react with water. PA6 membranes with KCl and CaCl2showed lower water vapor permeations as compared to hybrid membranes due to the increase in the size and quantity of pores presented on their top surfaces. The distilled water flow in the membranes initially showed a decrease and after 30 minutes a stability of the permeate flow due to a compression occurred in the membranes. The water-oil separation tests of the membranes with CaCl2, regardless of the pressure used, indicated a significant reduction of permeate oil with promising yields above 87% , presenting potential for the treatment of wastewater contaminated by oil.

Atualmente, os polímeros vêm sendo reforçados com fibras naturais, visando a geração de uma classe de novos materiais menos agressivos ao meio ambiente. Portanto, este trabalho teve como objetivo desenvolver compostos de biopolietileno (BioPE)/línter de algodão, compatibilizados com o polietileno enxertado com anidrido maleico (PE-g-MA). Os compostos foram preparados, inicialmente, em uma extrusora de rosca dupla corrotacional e, posteriormente, os grânulos extrudados foram moldados por injeção. As propriedades mecânicas (impacto e tração), temperatura de deflexão térmica (HDT), temperatura de amolecimento Vicat (TAV), calorimetria exploratória diferencial (DSC), ângulo de contato e microscopia eletrônica de varredura (MEV) foram avaliadas. Observou-se um aumento discreto no módulo elástico, na resistência à tração, na HDT e na TAV dos compostos, em relação ao BioPE puro. Todavia, houve perdas na resistência ao impacto. A presença do PE-g-MA e do línter aumentou o grau de cristalinidade dos compostos, em comparação ao BioPE. Os compostos compatibilizados apresentaram partículas de línter conectadas com a matriz de BioPE, indicando possíveis interações entre o anidrido maleico e os grupos hidroxilas do línter. Resultados aprimorados foram alcançados quando se utilizou PE-g-MA com maior grau de enxertia, sugerindo que a funcionalização impacta nas propriedades mecânicas e térmicas dos compostos.