Characterization of solid residues emerging during ultrasonic cleaning treatments of tyre moulds

The present paper aims at the investigation of the nature and possible origin of solid residues found in the washing basins of Ultrasonic Mould Cleaning System (UMCS) plants. In particular, analyses have been focused on the potential PTFE provenience of the debris and the eventual effect of acid solutions used in the process. Moreover, spring vents taken apart from tyre moulds subjected to repeated use and cleaning cycles, have been analysed in order to determine signs of wear, damage extent and its possible causes. Analyses have been performed by means of FT-IR, TGA, SEM-EDX and XRF, obtaining information on both organic and inorganic fractions. Results obtained seem to indicate that the degradation of PTFE is not responsible of the presence of these debris, and the acid solutions used in the process appear not to have a significant or direct role in the degradation and oxidation patterns.