and a jacket temperature of 170 u00b0 c and a second stage heat exchanger jacket temperature of 250 u00b0 c into a vacuum chamber maintained at 11 mm hg total pressure the polymer is pumped through a multi orifice stranding die into a water bath cooler and then through a cutter the average polymer collection rate will be 11 500 lbs hr the polystyrene product will have a residual monomer content below 10 ppm 1 narrow distribution polystyrene ps nd mw 189 000 mn 162 000 mw mn 1 17 prepared following the procedure of example 1 the resins were weighed out tumble mixed and dried at 80 u00b0 c for 16 hours the blends were compounded on a 0 8 inch w e twin screw extruder operating at these conditions ______________________________________zone 1 2 3 4 5 6______________________________________temp 230 240 250 260 270 280 u00b0 c rpm 250 double pass______________________________________ the pellets were again dried and compression molded at 450 u00b0 f then tested according to astm standards these blend properties were found ______________________________________1 2 3 4 invention prior art invention prior art ______________________________________ ppo 40 40 32 3 32 3 ps cg 60 48 5 ps nd 60 48 5 sbgr 19 2 19 2fm psi 4 57 u00d7 10 sup 5.