Processing and characterization of reclaimed rubber composite materials

Abstract

The dynamic mechanical properties of environment-friendly elastomeric composites consisting of reclaimed rubber (r-rubber), a waste product of roller processing of textile mill, and organic hindered phenol compound 4,4′-thio-bis(6-tert-butyl-m-methyl phenol) (AO-300) were investigated. With incorporation of AO-300 into the r-rubber, the storage modulus (E′) and loss modulus (E′′) of r-rubber were found to increase sharply, the maximum loss factor (tanδ) peak value increased from 0.49 to 1.01, and tanδ peak position was significantly shifted from 6.19 to 34.42 °C, indicating that r-rubber/AO-300 composite is a promising damping material. Furthermore, r-rubber/AO-300 systems exhibited an exceptional damping performance in the wide temperature range and with increasing AO-300 content, the effective temperature range increased from 55.32 to 63.14 °C. Meanwhile, the presence of intermolecular hydrogen bonds in the composite was confirmed by FTIR. Furthermore, from the SEM analysis of various r-rubber/AO-300 systems, it could be seen that by introduction of a small amount of AO-300 to the r-rubber, a typical complex morphology and hybrid state were coexistent in the composites. When the AO-300 content was larger than the critical value, more excess AO-300 molecules were crystallized. Thus, a new type of environment-friendly r-rubber based high-performance damping materials with a broad temperature range of damping behavior was developed.