General influence of the environmental temperature on the matrix strength under tensile and compressive loading - A comprehensive study on high performance matrices

Abstract

This comprehensive experimental study investigates the influence of operating temperatures ranging from −50 °C to 256 °C on the mechanical properties of various high-performance thermosets regularly used as matrix polymers for composites. The resins are either crucial for specific industry sectors or challenging to obtain because they are part of commercial prepreg systems. The research focuses on the temperature-dependent tensile and compressive strength of those materials and provides a wide database of mechanical properties. This paper summarizes the mechanical properties on the one hand in terms of a strength versus temperature scale, which allows an easy comparison for engineering applications. And on the other hand, it demonstrates that the thermo-mechanical properties are mainly dependent on the polymer's glass transition temperature. More precisely, three approaches to estimate the temperature dependence of the strength of thermosets with reduced testing effort are applied and presented. While one is based on the assumption that strength depends linearly on the environmental temperature, the others focus on the distance or the ratio of the environmental temperature to the glass transition temperature. This data set and the resulting correlations provide the community with valuable material data and allow to forecast the thermo-mechanical behavior of most thermosets in the future with significantly reduced effort.