Compatibilizing thermoplastic/ground tyre rubber powder blends: Efficiency and limits

Abstract : This paper deals with the compatibilization between recycled HDPE matrix and ground tyre rubber powder, through a free radical mechanism, by adding a peroxide. Mechanical tests show competition between the crosslinking of HDPE and the formation of interfacial bonding. The addition of more than 1 %wt of peroxide results in a strong improvement of interfacial adhesion and elongation at break. The performance is also compared to that resulting from gamma irradiation of the same blends. In the second part of this article, experimental tests and simulation by finite elements analysis were performed and showed the non-possibility of obtaining a “thermoplastic elastomer” by blending and compatibilizing HDPE and ground tyre rubber powder, since perfect interfacial adhesion still results in decohesion between matrix and particles.