Compatibilizing effect and reinforcing efficiency of nanosilica on ethylene‐propylene diene monomer/chloroprene rubber blends

Abstract This study shows an approach of compatibilization between ethylene‐propylene diene monomer (EPDM) and Chloroprene Rubber (CR) by using nanosilica (SiO₂) as a compatibilizer and, at the same time, as a strong reinforcing nanofiller. The effect of nanosilica and rubber composition was studied on microstructure and mechanical properties of the cured EPDM/CR/SiO₂. The microstructure of compounds were characterized using scanning electron microscopy and transmission electron microscopy, which demonstrated that the observed nanoSiO₂ were in both EPDM and CR phases. It was found that the addition of nanosilica had massive improvement on modulus, tensile strength, and dynamic mechanical thermal analysis of the samples. With the incorporation of just 10 phr nano‐SiO₂, the storage modulus above the glass transition region of CR50 increased from about 3.9 to 7.16 MPa. Moreover, the investigation of glass transition temperature (T_g) values showed that the compatibility of EPDM and CR in the compound enhanced with the addition of nanosilica, which in turn contributes to improving the properties of compounds. In addition, the results of mechanical properties of the samples revealed that the tensile strength, elongation at break and modulus of CR50 after modifying with 10 phr of nanosilica increased by around 398%, 33%, and 135%, respectively.