Ultra-violet Method for the Determination of the RTD in a Twin Screw Extruder
2011-10-4
The stereoselective replacement of chlorine atoms is used to graft anthracene and phenyl groups with the poly(vinyl chloride) (PVC) backbone as ultra-violet (UV) tracer to assess the residence time distribution (RTD) of PVC chains during the extrusion process of unplasticized and plasticized PVC. The residence time distribution gained using the grafted tracers is compared with that gained using a free UV tracer (anthracene). The polymeric tracer features a narrower RTD and a shorter mean residence time. This difference between free and grafted tracers is attributed to the compatibility of tracers with PVC.