Structure and Properties of a Modular Epoxy-Based Injection Resin
Based on lightweighting potential, there is a strong demand for fiber reinforced plastics. Today, a variety of resin systems are available commercially for industry to choose from. However, for wider applicability the costs must be reduced; the fiber should be used anisotropically and the qualification efforts decreased. The aim of this study is, through the use of a flexible base epoxy resin system, to demonstrate the structure-property effects of various formulation components influencing reactivity, mold release behavior, toughness and flammability. These novel, non-commercial epoxy resin formulations were systematically varied and the relationships between chemical structure of the components, the processing parameters and the composite properties established.
For example, the open time can be adjusted through the appropriate combination of accelerator concentration and mold temperature, without changing the chemical backbone of the cross-linked network. A test set-up allowing for a comparative investigation of internal mold release agents was constructed, validated, and one release agent was identified as a top performer.
Of the variety of toughening concepts tested, core-shell particles and dendrites were found to be the most effective. A direct correlation between flame retardant concentration and network density was also found, in addition to the correlation with reduced flammability. However, these formulations are borderline in terms of processability on an industrial scale. Additionally, liquid flame retardants were found to increase glass transition temperature through a post crosslinking effect.
Combining flame retardants and toughness modifier in one formulation, resulted in good mechanical properties but again the viscosity was too high for industrial processing by traditional LCM methods.
This thesis shows the possibility to tailor material properties without changing the base resin and hardener monomers of epoxy networks.Lesen Sie die deutsche Zusammenfassung auf Kunststoffe.de
Composite, Epoxy, RTM, flame retardancy, toughness
Institute / chair: Fakultät für Ingenieurwissenschaften der Universität Bayreuth
Technical consultant for expert services: Prof. Dr.-Ing. Volker Altstädt (Betreuer), Prof. Dr. rer. nat. Manfred Döring
Publication year: 2016
Provider: Wissenschaftlicher Arbeitskreis Kunststofftechnik (WAK) / Kunststoffe.de
About the PhD Dissertation Data Base
In cooperation with the Wissenschaftlicher Arbeitskreis Kunststofftechnik (WAK), we provide free access to current dissertations in the field of plastics technology.