Acrylonitrile butadiene rubber and high styrene resin - Rheological behaviour of composites

The rheological behaviour of composites based on acrylonitrile butadiene ru bber (NBR) and high styrene resin (HSR) has been studied by using a Monsant o Processibility Tester. All the systems show pseudoplastic flow behaviour. It has been observed that the die swell increases with an increase in shea r rate and decreases with an increasing wt % of HSR and temperature. The ma ximum recoverable deformation were calculated by assuming that the viscous response of the rubbers obeys the power law model, and elastic behaviour is described by Hooke's law. Correlating with the die swell, a linear general ized relationship was obtained between the die swell and the recoverable de formation. The principal normal stress difference was found to increase lin early with shear stress. The activation energy of the melt flow process dec reases with an increase in both shear rate and HSR content.