A method is presented to predict the yield stress distribution throughout an injection molded product of an amorphous polymer as it results from processing conditions. The method employs the concept of structural relaxation combined with a fictive temperature following the Tool-Narayanaswamy-Moynihan formalism. The thermal history, as it is experienced by the material during processing, is obtained by means of numerical simulation of the injection molding process. The resulting predictions of yield stress distributions show to be in excellent agreement with experimental findings, both for different mold temperatures, as for different part thicknesses.
|Journal||Journal of Polymer Science, Part B: Polymer Physics|
|Publication status||Published - 2006|