Pultrusion of thermoplastic composites - New developments and modelling studies

Abstract

Objective of this study is to present new developments in thermoplastic pultrusion (a pullbraiding process combined with a contact preheating system, and a new online forming method for pultruded profiles) and a new approach for modelling of the preheating process. After modelling of the preheating process of commingled glass fiber/polypropylene yarn, the preheating of a thermoplastic pultrusion line to produce profiles with unidirectional reinforcement in axial direction was modified by adding contact heating pins. Compared to the convective heating used before, profiles with higher qualities could be produced at three times higher processing speeds. First trials of a combined braiding and pultrusion process, also with contact preheating, led to promising results. Furthermore, a process to post-form pultruded profiles immediately after leaving the heated pultrusion die was developed, leading to profiles with a forming radius of 10 cm.