Obtenção de um revestimento compósito de poliéster-uretana reforçado com alumina pela técnica de deposição por imersão sobre fibras de poliamida 6

Abstract

ResumoO uso de revestimentos compósitos de matriz polimérica e reforço cerâmico capazes de manter a flexibilidade e a elasticidade das fibras poliméricas, agregando propriedades típicas dos materiais cerâmicos (como ação bactericida ou fotocatalítica, resistência à chama, ao desgaste e à abrasão), tem atraído interesse da indústria têxtil. Baseado na técnica dip coating e usando fibras sintéticas de poliamida como substrato, foram produzidas suspensões de poliéster-uretana com partículas de alumina (tamanho médio de partícula 2,2 µm) para obtenção de revestimentos uniformes e espessos sobre o material base, poliamida 6. A viscosidade das suspensões foi controlada pela adição de carboximetilcelulose e avaliada por reometria rotacional. A distribuição granulométrica das suspensões também foi determinada. Os parâmetros operacionais do dip coating, i.e., velocidade de bobinamento e temperatura dos fornos, foram mantidos constantes em todas as amostras. O processo mostrou viabilidade para deposição uniforme do recobrimento avaliado, com espessura adequada, indicando ser promissor para revestir fibras, agregando propriedades de interesse tecnológico. Palavras-chave: revestimentos compósitos, barbotinas, dip coating, alumina, fibras sintéticas. AbstractCeramic reinforced polymer composite coatings that can retain the flexibility and elasticity of the polymeric fibers, being also able to incorporate the functionality of ceramic materials (e.g. fire, wear, or abrasion resistance, antibacterial performance, photocatalytic effect) are interesting to the processing of textile materials. In this work, polyester-urethane slurries with alumina particles (mean particle size: 2.2 µm) were developed based on the dip coating technique and using polyamide-6 synthetic fibers as the substrate, seeking to obtain an uniform and thick coating. The viscosity of the slurries was varied using carboxymethylcellulose as a rheological agent and evaluated by rotational rheometry. Particle size distribution of the slurries was also analyzed. The developed process successfully deposited a thick and homogeneous composite coating on the fibers, which has the potential of enhancing the original fiber properties and the technological interest towards this material.

A review of Corrosion Resistance Nanocomposite Coatings

“…All of these processes aim to achieve coatings with improved uniformity, good reproducibility, high adhesion, high deposition rate, low roughness, and low cost [12][13][14][15]. It is important to mention that these features, as well as the coating morphology and microstructure, the incorporated particle size (particle clusters), and the amount of particle in the coating, depend on both the substrate and the deposition process used to produce the MMC coatings, influencing the properties of the coating/substrate system [16][17][18][19][20][21][22]. Table 1 presents some examples of MMC coatings produced with different deposition processes and the main results achieved by the researchers.…”