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In this work, PVDF composites containing 0.2% (m/m) of carbon nanotubes (MWCNTs), PVDF with 5.0% (m/m) of zinc oxide (ZnO), and composites containing both particles in the same contents in the matrix were melt processed in a mini-extruder machine with double screws, using the counter-rotation mode. Composites were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), dynamic-mechanical analysis (DMA), and contact angle tests (CA). The samples presented the predominance of the α phase, with an increased degree of crystallinity as well as an increase in dimensional stability by incorporating both fillers, showing a synergistic effect between these particles, as shown on FTIR, DSC, and XRD results. SEM images showed a good dispersion of high aspect ratio particles. In general, DMA and TGA analysis showed that composites had not decreased their thermal and mechanical performance when compared to neat PVDF. Results of CA analysis showed an increase in the hydrophobicity of the sample containing MWCNTs. Permeability tests were also performed using a differential pressure system, combining high temperature and pressure, obtaining permeability measures and time lag. This work presents an alternative of composite materials, suggesting its application in the internal pressure sheath layers of oil and gas flexible pipes. K E Y W O R D S composites, nanoparticles, nanotubes, oil and gas, thermoplastics 1 | INTRODUCTION Flexible pipes are transportation lines used to connect the wells, in the seabed, to the production units, transporting oil and gas fluids in offshore applications. These pipes possess a multilayer structure, with polymeric layers and helically wound metallic wires, designed to withstand tensile loads, high pressure, and temperature. 1-3 Different layer combinations are possible, depending on the intended service conditions. Still, in general, flexible risers present a typical configuration, with the following layers: interlocked carcass (metal),

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Atualmente muito se discute sobre os impactos ambientais causados pelo descarte dos plásticos. A falta de conhecimento, o desinteresse pelo problema e a falta de oportunidade para amenizá-lo, são significativos empecilhos para melhora deste quadro na sociedade. No ensino de Química, elucidam-se conceitos relacionados a muitos destes materiais descartados de maneira imprópria. A necessidade de ressaltar a conscientização dos alunos, independente de série escolar, sobre a necessidade da prática do reuso de plásticos e em especial a importância da reutilização das garrafas PET contribui para a formação de cidadãos mais críticos e atuantes na sociedade. No presente trabalho é descrita a realização de uma exposição de ciências a partir da reutilização de polímeros, como forma de conscientização dos males que o descarte de plásticos pode gerar para o meio ambiente. Todo o trabalho foi desenvolvido com cooperação de um grupo de alunos do segundo ano do ensino médio, da Escola Estadual Vila Bela no município de Mesquita, Rio de Janeiro. Estes foram os colaboradores principais do projeto, trouxeram grande parte dos materiais utilizados, estudaram o tema em questão e auxiliaram na confecção dos objetos expostos. O trabalho tem como objetivo ressaltar o ensino de química interligado a conscientização ambiental, através da problematização do descarte indevido de plásticos em seu cotidiano a partir de uma exposição com materiais reciclados.

In this work, the preparation and characterization of nanocomposites of commercial polyamide‐11 reinforced with multi‐walled carbon nanotubes (MWCNT), untreated, oxidized or with the modified surface through silanization with 3‐aminopropyl trimethoxy silane (APTMS), in concentrations of 0.1%, 0.5%, and 1.0 wt% in the polymer matrix was investigated. The processing of the nanocomposites was carried out via mixing in the molten state in a twin‐screw mini‐extruder at 200°C under 60 rpm screw rotation speed, with a residence time of 7 min. The addition of the MWCNT increased the thermal stability of PA11, predominantly with 0.5% of silanized nanotubes, as observed by the thermogravimetric analysis. X‐ray diffraction and differential scanning calorimetry analyses indicated that the degree of crystallinity of the formulations increased with the nanofiller content. On the other hand, the use of the highest concentration generated agglomerates, suggesting less dispersion in the matrix and, consequently, a reduction in crystallinity. Dynamic mechanical thermal analysis showed that the silanization process promoted an increase in both loss and storage moduli. All produced nanocomposites obtained values of corrected inherent viscosity above 1.20 dl/g, before and after the aging test. The use of lower load levels promoted better processability due to the lubricating effect of the nanotubes and an increase in the hydrophobic character of the samples, as observed by the increase of the contact angle.