BLENDS OF POLYETHYLENE-POLYISOPRENE RUBBERS - STUDY OF FLOW PROPERTIES

Dynamic shear properties of thermoplastic elastomers from blends of po lyethylene-polyisoprene rubbers were studied over a range of frequenci es and temperatures. eta decreased with frequency and temperature and increased with rubber content in the blend. G' increased with frequen cy and with rubber content in the blend and decreased with temperature . Tan delta became equal to 1 at lower frequencies, as the rubber cont ent increased. Plots of G' versus G '' (Cole-Cole plots) superimposed at rubber contents of 30% and below, indicating compatibility at these concentrations. Viscosity measurements at high shear rate were obtain ed from capillary rheometry. The effect of the rubber type and the ble nd ratio on those properties was determined. The morphology of the ble nds was also studied by scanning electron microscopy, where two phases were clearly observed.