Recuperação de borracha EPDM utilizando EPDM modificado com dodecanotiol como agente compatibilizante

Abstract

In this work, the compatibilization technique was employed to recycle the ethylenepropylene- ethylidenenorbonene (EPDMR) vulcanized rubber. For this purpose, ethylenepropylene ethylidenenorbonene (EPDM) functionalized with dodecanethiol (EPDMDDSH) was prepared and used with compatibilizing agent. EPDM compositions containing EPDMR in different proportions were prepared in a roll mill at 70ºC and 50 rpm. EPDMR was added as filler in the EPDM virgin rubber and 5 phr of the EPDMDDSH were used as compatibilizer. The rheometric study suggests that EPDMDDSH do not act as a vulcanized accelerator. This study also revealed the participation of EPDMR on vulcanization reactions due to the presence of carbon black in their compositions. The mechanical properties results showed that the addition of 5 phr of EPDMDDSH at different EPDMR compositions produced an improvement on tensile strength, elongation at break and tear strength properties. The information gotten on the processing of the mixtures, using an analyzer of rubber processing (RPA), indicate that the EPDMDDSH addition does not modify the elastic and viscous modulus, as well as the viscosity of the mixture. However, increases of elastic and viscosity modulus were observed with increase on EPDMR content.