https://popups.uliege.be/esaform21/index.php?id=4255 Index terms fr 0 https://popups.uliege.be/esaform21/index.php?id=970 Pultrusion is an established and efficient process for producing continuous fiber-reinforced composites. The resin systems that are currently most frequently used are unsaturated polyesters and vinylesters. These have a long pot life, are well known, and have good processing properties. Highly reactive resins such as polyurethane (PU) and amine hardening epoxy have been in use for a few years. These resin classes are remarkable for their extended range of properties. This opens up new application fields for pultrusion technology but poses challenges for the processing technology. Short pot lives of just a few minutes require a modified process: closed injection pultrusion (CIP). Various approaches about the design and layout of the internal geometry of the injection and impregnation chambers (ii-chamber) are the subject of ongoing research. Numerous parameters influence the impregnation process in the ii-chamber and the quality of the resulting composite. In this study, two innovative, highly reactive resins for use in the pultrusion process were analyzed, both resins based on aliphatic polyurethanes. In phase 1 of the experiments, a commercial aliphatic polyurethane-system for pultrusion applications was used. In Phase 2, the recently developed bio-based aliphatic polyurethane-system for pultrusion applications was used for the study's main experiments. The aim of the study was to analyze the material and processing properties with various modifications of the impregnation setup. Therefore, a newly developed ii-chamber and die were tested. The ii-chamber was designed to enable easy adjustment of some of the main influencing parameters during the pultrusion process. A test strategy was developed to evaluate the properties of the composites. An assessment of the influence of the process- and die-based parameters should enable an evaluation of the optimal processing settings by analysis of the material characteristics. The most significant effect of variations in the pultrusion process was found in the interlaminar shear strength (ILSS). ILSS was analyzed for all process variations for both resin systems. Mon, 22 Mar 2021 10:44:54 +0100 Fri, 02 Apr 2021 17:40:12 +0200 https://popups.uliege.be/esaform21/index.php?id=970 https://popups.uliege.be/esaform21/index.php?id=4252 The use of reinforcing bars has been known for more than 150 years in construction sector, in order to compensate the limited tensile strength of concrete. Steel is the most widespread and standardized rebar material. As industry targets a reduction of resource consumption and increased freedom of design, novel materials come into the scope of current research efforts. In this context, carbon fiber reinforced polymers (CFRP) have become a promising candidate for rebar materials as they offer excellent corrosion resistance and mechanical properties. Their use enables significant reduction of concrete cover in future buildings and cost-efficient maintenance of bridges. The resin system used for manufacturing of CFRP rebars dictates possible applications. Thermoplastic polymers offer the advantage of formability in a molten state. On the other hand, they provide limited heat and fire resistance, what hinders further industrialization. In contrast, thermosets deliver high mechanical and thermal properties due to their polymeric network structure. This is also the reason for their restricted formability after gelation has occurred. However, it is known that epoxy resins may sustain substantial plastic deformation when being deformed at elevated temperatures and in a partial cure state. In this work, a commercially available resin system is selected and qualified for potential use in thermoset-based CFRP rebars. Based on the resin characterization comprising reaction kinetics as well as tensile and compressive tests at partial cure, general guidelines and limits for secondary forming are derived. The feasibility is demonstrated by bending tests on CFRP stripes with varied fiber orientation. Thu, 01 Apr 2021 17:32:01 +0200 Thu, 01 Apr 2021 17:32:01 +0200 https://popups.uliege.be/esaform21/index.php?id=4252