Investigación del comportamiento antiestático del polímeros extrínsecamente conductores basados en polipropileno

Abstract

[ES] El objetivo del trabajo es poder fabricar materiales plásticos con capacidad antiestática mediante procesado en impresión 3D. Para este fin se añadirán como cargas conductoras nanotubos y nanofibras de carbono a una matriz termoplástica convencional. Se procederá a optimizar la concentración de cargas con el objeto de reducir al máximo su contenido. Se medirá la conductividad eléctrica de las muestras así como el tiempo de decaimiento de la carga estática. Además se aplicará un tratamiento térmico a las muestras para mejorar los resultados y se a analizará su comportamiento térmico. Por último se modelizará el comportamiento eléctrico por medio de modelos basados en al teoría de la percolación.

[EN] Polymers are materials by nature insulating. In many cases, this property is beneficial, although it has its disadvantages. By being insulators these materials, retain a large amount of static electricity on their surface. There are many research projects that try that these polymers are no longer insulating, since there are many applications in different sectors. It is very visible in the area of telephony (OLED screens). It is also necessary increasingly the use of dissipative materials of electrical charge in movable elements of machines since a large accumulation of electric charge can result in an electrostatic discharge (ESD) a phenomenon that can break the internal circuits of the machines. In the present work, we study the electrical and thermal properties of a polypropylene polymer matrix with two different charges, carbon nanofibers (GANF) and carbon nanotubes CNT). Different percentages have been studied between 2 and 20% for both nanotubes and nanofibers. In addition, the samples have been subjected to a heat treatment whose percentages studied have been between 0.5 to 2% in the case of carbon nanotubes and 0.2% to 20% for carbon nanofibers. The electrical properties of the material have been studied with two different approaches; The resistivity of the material has been measured and, in addition, the decay time of the electric harge on the surface of the material for each percentage has been measured. An improvement in the resistivities of the material is observed when these are submitted to the thermal treatment. With the knowledge acquired in the present work, the electrical capacities of a plate made by 3D printing are finally checked, in order to know if it is feasible to use 3D printers to print parts with dissipative capacity of the electric charge.