Development of an intermediate layer for multilayer hoses used in turbo lines of motor vehicles

Multilayer hoses for turbo lines can be produced by ethylene acrylic rubber (AEM) as the inner layer and peroxide cured ethylene propylene diene monomer (EPDM) as the outer layer. In such a case, the polar AEM should adhere well to the apolar EPDM to ensure proper functioning. In this work, new blends were developed and optimized to offer potential for using as intermediate bonding layers. Different compositions of dipolymer AEM/EPDM and terpolymer AEM/EPDM blends with and without maleic anhydride grafted EPDM (Ma-g-EPDM) as a compatibilizer were successfully prepared. Curing behaviors, as well as mechanical and thermal properties of the blends were investigated in detail. The effects of the compatibilizer addition were also explored by dynamical mechanical analysis, DeMattia and scanning electron microscope. It is found that Ma-g-EPDM is more effective in terpolymer AEM containing blends. Additionally, 60/40:AEM/EPDM weight ratio is the most suitable proportion for turbo lines.