Development of emission factors for polypropylene processing

Emission factors for selected volatile organic compounds and particulate emissions were developed during extrusion of commercial grades of propylene homopolymers and copolymers with ethylene. A small commercial extruder was used. Polymer melt temperatures ranged from 400 to 605 degrees F However, temperatures in excess of 510 degrees F for polypropylene are considered extreme. Temperatures as high as 605 degrees F are only used for very specialized applications, for example, melt-blown fibers. Therefore, use of this data should be matched with the resin manufacturers' recommendations. An emission factor was calculated for each substance measured and reported as pounds released to the atmosphere per million pounds of polymer processed [ppm (wt/wt)]. Based on production volumes, these emission factors can be used by processors to estimate emission quantities from polypropylene extrusion operations that are similar to the resins and the conditions used in this study.