Fundamentals of Electron Microscopy of Heterogeneous Elastomer Blends. II

Abstract Electron and phase microscopy results show that most elastomer blends are heterogeneous, even after extended mixing. Blends of SBR/BR and SBR/EBR, however, are homogeneous. DTA data support these conclusions. Carbon black distribution studies indicate that carbon black does not transfer between elastomers during mixing. Polychloroprene exhibited a strong affinity for carbon black in blends with natural rubber. In this system, with the black predispersed in the natural rubber, the carbon black particles were observed at the polychloroprene interface but had not entered that phase.