Efeito da adição de pentóxido de nióbio e fosfato de cálcio nas propriedades do polipropileno

Abstract

Polymeric composites filled with inorganic particles, which generally have high melting temperatures, high hardness and biological inertia, have attracted great interest from research centers and industries, due to the great potential of technological innovation that this combination of materials presents. It is within this context, that studies aiming at obtaining materials with higher added value based on niobium oxide have been encouraged, since Brazil holds more than 90% of the world's reserves of this element. In this work, polypropylene composites filled with niobium oxide were developed in order to find new applications for these materials. The results showed that the niobium oxide promoted an increase in tensile strength, modulus of elasticity and toughness of the polypropylene. The impact strength of polypropylene, however, did not change significantly under the experimental conditions used. The inorganic filler also promoted the thermal stability of the polymer. These characteristics suggest possible applications in the automotive, civil construction, microelectronics packaging industry, biomaterials, among others. As the composites obtained showed high stiffness and an elevated elongation at break, the development of polypropylene hybrid composites filled with niobium oxide and calcium phosphate were also developed, aiming applications in the area of biomaterials. The addition of niobium oxide to the polypropylene filled with phosphate carbonate composites aims to increase the toughness of these materials for applications in biomaterials, such as bone substitutes, dental implants, among others. On the other hand, calcium phosphate may promote the biocompatibility of niobium oxide composites with the human body. The results obtained showed that the addition of calcium phosphate to the polypropylene composites with filled niobium oxide did not significantly modify the tensile properties, but caused a considerable reduction of the elongation at break and the impact strength. The thermal properties were not significantly altered. The composites obtained did not present the formation of biofilms on the surface of the samples. The obtained materials have the possibility of being used as biomaterials, if a antibacterial agent is added to the composites.