Title: Thermoplastic Towpregs - An Investigation of the Hot Melt Production Process

Authors: Ing. Thomas Gries, Max Schmidt, Kai Cramer

DOI: 10.33599/nasampe/s.21.0426

Abstract: The impregnation of thermoplastic fiber composites usually requires heavy and expensive machinery. This still restricts the use of FKV in many areas. To reduce manufacturing costs, towpregs are used: they are of consistently high quality and require comparatively simple manufacturing steps. In this paper a process developed at the Institute for Textile Technology for the production of thermoplastic towpregs is researched. In order to achieve the goal of a complete impregnation of the rovings a special tool was developed which serves as a basis for this paper. Due to the geometry of the tool, the carbon fibers are guided in a special way through the hot thermoplastic filled cavity. In order to control further parameters, a closed loop control for the roving guidance was developed and integrated into the machine. In detailed process investigations the pull-off force, production speed and sizing were identified as primary process relevant parameters of the melt impregnation. Their influence was researched and evaluated. The impregnation tool produced in the course of the work has completely impregnated carbon fibers of different fineness with thermoplastic. Finally, the towpregs produced on laboratory scale were validated by evaluating optical and mechanical tests. The measurements show promising tensile strengths of the manufactured towpregs. These are in the range of the tensile strength of the fibers as stated by the manufacturer. First application tests show that they are suitable for winding processes or as a replacement for steel in ropes.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000426

Pages: 20

Price: FREE