pps proceeding - Abstract Preview
pps proceeding
Symposium: Modeling & Simulation
Poster Presentation
 
 

A new analytical material model for the coefficient of thermal expansion for semi crystalline polymers.

van Dorp Esther (1)*, Steinhaus Johannes (1), Reith Dirk (1), Bruch Olaf (2), Hausnerova Berenika (3), Moeginger Bernhard (1)

(1) University of Applied Sciences Bonn-Rhein-Sieg - NRW - Germany, (2) Dr. Reinhold Hagen Stiftung - NRW - Germany, (3) Tomas Bata University Zlin - Zlin - Czech

Although extrusion blow molding is a successful processing method for more than 30 years to produce hollow plastic parts for the packaging and automotive industry, until today no proper simulation software has been developed as it is used for the injection molding industry. A very important material characteristic that determines the thermal behavior of plastic parts is the coefficient of thermal expansion (CTE). This study will propose a new way to describe the CTE as an analytical material model for semi crystalline polymers applied on HDPE. The aim is to develop an analytical material model to describe the processing dependent thermal performance to be later inserted in and improving the existing FEM-simulation methods for extrusion blow molding. Material used for this study was high density polyethylene (HD-PE) because up to 80% of all extrusion blow molded parts are made of HD-PE. Differential Scanning Calorimetry (DSC) and Thermomechanical Analysis (TMA) are used to characterize the thermal properties of HD-PE. These results are correlated with the material model providing a better overview of the structure-properties relationship. Comparison between the material model predicted results and the experimental measured values for two different types of HD-PE, yields good agreement.