through a line 10 the intrinsic viscosity or molecular weight of the starting material is immaterial to the practice of the invention generally the ssp process can be successfully performed with feeds across a wide range of values for example techniques are disclosed for using a starting material having a degree of polymerization as low as 2 40 by u s pat no 5 540 868 u s pat no 5 633 018 and u s pat no 5 744 074 which contemplate eventually undergoing ssp processing to raise the molecular weight sufficient to make useful resins also the starting intrinsic viscosity in the case of post consumer recycle material can be at levels of above 0 65 dl g the hopper 12 feeds the chips through a line 14 and a control valve 16 to an optional pre crystallization zone 18 then through line 19 to a rotary processor or kiln 20 if additional polymerization is desired the chips and then fed to an optional reactor 22 through a line 23 and the polymerization may be quenched in a product cooling or quenching station 24 in chip flow communication through line 25 a gas purification and pumping system 26 is connected to the various vessels and components of the plant 5 through lines 28 however it is envisioned that all crystallization and polymerization be achieved in the rotary kiln 20 without need for the pre crystallization zone 18 or the reactor 22 the hopper 12 is of conventional design having.