On the use of micro thermal analysis to characterize compatibility of nitrile rubber blends

The paper describes the use of micro thermal analyzer (μTA) for assessment of compatibilization in blends of nitrile rubber (NBR) with neat high-density polyethylene (HDPE), phenolic resin modified together with dynamically vulcanized HDPE and polyvinyl chloride (PVC). Micro thermal analyzer (μTA) was employed to identify different locations by the study of thermal conductivity of the surface and topographic features. Local thermal analysis (LTA), e.g., micro thermomechanical analysis (μTMA) and micro differential thermal analysis (μDTA), were conducted at these locations. Blending of NBR with unmodified HDPE shows incompatibility. Modification of HDPE by phenolic resin and dynamic cross-linking by peroxide resulted in technological compatibilization of the blend, while NBR and PVC generated characteristics of a miscible blend.