Este trabalho tem como objetivo estudar o efeito de cordonéis de poliéster, poliamida, poliaramida e híbrido poliamida/poliaramida como reforço de elastômeros utilizados na fabricação de mangotes. O comportamento do tubo elastomérico reforçado com cordonéis sob pressão interna foi simulado com análise por elementos finitos (FEA) utilizando-se elementos chamados reinforcement bars. Foram realizados ensaios para se obter as propriedades em tração dos cordonéis para alimentar o modelo. O cordonel de poliaramida apresentou a maior tensão de ruptura, o de poliamida maior deformação na ruptura, e o híbrido apresentou valores intermediários. O critério de falha adotado para o tubo consistiu na análise do nível de carga no cordonel. Foram avaliadas, principalmente, a pressão e a deformação de ruptura do tubo elastomérico simulado frente à variação do ângulo de orientação dos cordonéis. Os resultados mostraram que ângulos próximos a 55° tornam o tubo mais resistente porém menos rígido no sentido longitudinal.

This work investigates the effect of polyamide, polyester, polyaramid and hybrid (polyamide and polyaramid) cords as reinforcement for elastomers used in the production of marine hoses. The behavior of the elastomeric pipe reinforced with these cords under internal pressure was simulated with finite element analysis (FEA) using elements called reinforcement bars. To obtain input data for the model, tensile properties of the cords were evaluated. The polyaramid cord showed the highest ultimate stress, the polyamide the largest elongation at break, and the hybrid cord showed intermediate values. The failure criterion adopted for the pipe consisted of examining the allowable force in the cord. The analyses focused on the variation of pressure and strain at burst of the pipe with the orientation angle of the cords along the elastomeric tube. The results showed that angles close to 55° yielded stronger pipes but less rigid in their longitudinal direction.

In this work, hydroxyapatite (HAp) obtained from the deorganification of bovine bones using hot NaOH solution was used to synthesize a HAp/epoxy infiltrated composite. Infiltration was carried out by vacuum assisted immersion in hot epoxy resin. The resulting composite was characterized regarding polymer content, morphological aspects and flexural strength. The infiltration method used resulted in thorough infiltration of the HAp but some residual porosity remained. Although the epoxy resin showed good interaction with the HAp, high polymer content was achieved and the flexural strength of the composite was higher than that of the original resin or the HAp, composite strength was lower than that of the human cortical bone.