wt which was then diluted to a final concentration of 0 1 wt bn pellets of exact u00ae 3128 having 0 1 wt bn were mixed in dry form with calcium stearate this way the exact u00ae 3128 1 wt calcium stearate 0 1 wt bn blend product was prepared the exact u00ae 3128 1 wt calcium stearate blend was prepared by dry mixing of exact u00ae 3128 polyethylene pellets with calcium stearate the four flow curves are plotted shear stress versus shear rate in fig4 the flow curve of virgin exact u00ae 3128 the flow curve of exact u00ae 3128 with the addition of 0 1 bn the flow curve of exact u00ae 3128 with the addition of 1 calcium stearate and the flow curve of exact u00ae 3128 with the addition of 0 1 wt bn and 1 wt of calcium stearate are illustrated the test was run on the crosshead die attached to a rheometer the results are summarized in table 4 below in addition the use of calcium stearate in the combination with boron nitride decreases the extrusion pressure and therefore the extrusion becomes practically easier the experiment illustrated in example 4 was repeated with zinc stearate in place of calcium stearate the results were similar the use of.