Ten-year duration experiment of compression test kinetics of extruded polystyrene foam

This paper presents the data from a 10-year direct experiment. Extruded polystyrene foam (XPS) compression tests were performed during the experiment. In addition, the kinetics of short-term compressive stress (σ 10 % ) or strength (σ m ), strain (ɛ), and elastic modulus (E) were analysed. The results of their variations were evaluated, basic numerical values determined, and frequency diagrams obtained. It was found that the intensive growth of σ 10 % or σ m of XPS continued for approximately 365 days, and then there was only an insignificant change in σ 10 % or σ m values. An increase of up to 54.4 % was observed in σ 10 % or σ m values in the initial period, and only a 3.7 % increase was observed in the next nine years. Values of ɛ changed very similarly to σ 10 % or σ m . In contrast, the change of E occurred at a rate that was almost similar throughout the test period – the total increase of E during the investigated period was 15.9 %. Structural and spectroscopy studies evaluated changes in the strength indicators of XPS foams. Comparing the changes in the samples 10 days and 10 years after production, it became clear that the structure of the cell walls of the extruded foam changed, and new bonds formed. • An increase of 54.4 % is observed in compressive stress values in the initial period. • The elastic modulus occurs at an almost similar rate throughout the test period. • The deformation mechanisms of XPS change with time. • Chemical changes in XPS cell walls increase their strength values.