Investigation of the Orientation Behaviour of Liquid Crystalline Polymers in Fused Deposition Modeling

• Applicant: Professor Dr.-Ing. Christian Bonten
• Subject Area: Plastics Engineering
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 503938087

Additive manufacturing allows the production of components without a mold using various types of materials, whereby the components are produced layer by layer based on a three-dimensional computer model. In the field of plastics processing, fused deposition modeling is by far the most commonly used additive manufacturing process. Research work in the polymer-based fused depo-sition modeling has so far been concerned almost exclusively with the use of conventional poly-mers with flexible macromolecular chains. For high-strength components, high-performance ther-moplastics such as polyetheretherketones or polyetherimides are used in particular, whereby orien-tations introduced by the processing partially relax after nozzle exit for these polymers.In contrast to this, Liquid crystalline polymers (LCP) exhibit a certain preferred orientation even in the relaxed state due to their special molecular structure. Within the scope of this research proposal, the orientation behavior of LCP molecules in the fused deposition modeling process will be investi-gated experimentally and simulatively, in order to subsequently achieve high anisotropic mechani-cal properties in printed specimens. In doing so, it is to be investigated experimentally how both the path planning and the process parameters (e.g. printing temperature and filament speed) during fused deposition modeling influence the molecule orientations and thus the subsequent specimen properties. Numerical flow simulation by means of CFD is to be used to simulate both the melting and the cooling behavior in the fused deposition modeling process. These investigations thus form the scientific base for optimizing path planning strategies and process parameters in advance to the fused deposition modeling process in such a way that structural components exhibiting high tensile strength can be manufactured.

• DFG Programme: Research Grants