Análise do comportamento da poliamida 11 reciclada utilizada como revestimento automotivo

Abstract

Polyamide 11 is a polymer widely used for coating slip interfaces to protect against friction wear, since it has a good combination of chemical, thermal and mechanical properties. The automotive industry uses parts coated with melted polyamide in the form of a continuous coating. This work evaluates the viability of the primary recycling of waste from the machining of polyamide 11 used as a coating, in the form of mixtures with the virgin polymer, in the proportions of 100/0, 85/15 and 75/25 virgin and recycled PA11, respectively. The methods of characterization of virgin and recycled samples and their combinations are based on thermal analyzes (thermogravimetric and differential scanning calorimetry), hardness, roughness and adhesion analysis, as well as tribological wear analyzes. The isothermal and non-isothermal crystallization kinetics of the virgin and recycled polyamide 11 indicated that the crystallization rate of the recycled material is higher than the virgin material. Melting and degradation temperatures were maintained for both materials. The uniformity and adhesion of the coating were satisfactory, keeping in line with the parameters required for the automotive application. The technique of analysis of the infrared absorption region (FTIR) showed that there was no damage to the polymer binding. The tribological analysis showed a different behavior for the two antagonist body roughness s employed. The incorporation of recycled material decreased wear and maintained the coefficient of friction. The primary recycling of the polyamide residue 11 is feasible and its use reduces the cost with the raw material and the damages caused by the inadequate disposal of this residue.