Synthesis and application of AN-g-EPDM and AA-g-EPDM as compatibilizers for CR/EPDM and NBR/EPDM rubber blends

The graft polymerization of acrylonitrile (AN) or acrylic acid (AA) onto ethylene-propylene-diene terpolymer rubber (EPDM) was carried out in toluene, using dibenzoyl peroxide (BPO) as an initiator. The synthesized AN-g-EPDM and AA-g-EPDM were characterized by FT-IR spectroscopy and thermal gravimetric analysis (TGA). AN-g-EPDM and AA-g-EPDM were incorporated into chloroprene rubber (CR)/EPDM and butadiene acrylonitrile rubber (NBR)/ EPDM blends. The compatibility of EPDAVCR and EPDM/NBR blends was examined with scanning electron microscope (SEM) and differential scanning calorimetry (DSC). The physico-mechanical properties of the vulcanizates were investigated after and before thermal aging. AN-g-EPDM and AA-g-EPDM improved the morphology of CR/EPDM and NBR/EPDM rubber blends. The mechanical properties illustrate that the compatibilized blends possessed good thermal stability.