Assistance Machine Function for BMC Injection Molding

  • Nicolina TopicEmail author
  • Stefan Kruppa
  • Dietmar Drummer
Conference paper


Bulk molding compounds (BMC) are short fiber reinforced polyester molding compounds and mostly processed by injection molding. They consist essentially of polyester resin, styrene, additives, fillers and glass fibers and are fabricated in a conventional Z-kneader by mixing the resin and the solid fillers. Due to its doughy and moist consistency BMC requires force feeding to the barrel of the injection molding machine by a piston or screw stuffer. Furthermore, the raw material has a limited shelf life and needs special storage conditions. Because of the considerable proportion of volatile styrene, the dwell time of the material during processing is an important parameter. In this study the styrene loss is quantified during the injection molding production with a screw stuffer and evaluated for different loading scenarios. As a result, an assistance machine function is developed which optimizes the load operation in order to reduce the impact of styrene loss.


BMC Injection molding Styrene evaporation 



The presented investigations take place within the research project “Quality-optimized Production of Thermosets”, which is supported by the Bavarian Ministry of Economic Affairs and Media, Energy and Technology within the cluster “Neue Werkstoffe (BayNW)”. The cooperation partners are University of Applied Sciences Rosenheim, Deckerform Produktionssysteme GmbH and Gubesch Thermoforming GmbH. The authors acknowledge the input and support of the cooperation partners, the promoter as well as the Project Management Jülich.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2020

Authors and Affiliations

  • Nicolina Topic
    • 1
    Email author
  • Stefan Kruppa
    • 1
  • Dietmar Drummer
    • 2
  1. 1.KraussMaffei Technologies GmbHMunichGermany
  2. 2.Institute of Polymer TechnologyUniversity of Erlangen-NürnbergErlangen-TennenloheGermany

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