Dynamically vulcanized PP/EPDM blends: Influence of curing agents on the morphology evolution

Abstract

Abstract Thermoplastic vulcanizates (TPE‐Vs) are a special class of thermoplastic elastomers (TPEs), where the rubber phase is dynamically crosslinked in the presence of a thermoplastic matrix. The goal of this work is to compare the behavior of two curing agents systems, conventional peroxide named Peroximon and bismaleimide/dicumyl peroxide, in TPE‐Vs based on PP/EPDM 35/65 w/w. It was also investigated the TPE‐Vs morphological evolution and samples was collected at different times during the mixture and dynamic crosslinking. The materials were characterized by some techniques, which allowed investigating mechanical, morphological, hardness, and swelling properties. Considering the used curing agents contents, the TPE‐Vs obtained by using Peroximon presented lower tensile strength, lower swelling degree, and remarkable lower deformation than those obtained with BMI/DCP system. The hardness properties were not significantly affected by the content of the curing agent, showing only a slight decrease when the Peroximon content was increased. The study of the evolution of morphology showed the rubber phase undergoes crosslinking after adding the curing agent. It could be observed by the increase of the torque and by the appearance of domains in the micrographs. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008