Powder Modifier Effect on the Mechanical Behavior of Polyurethane Foams

The paper investigated the influence of a powder modifier in the form of finely dispersed perlite on the mechanical behavior of rigid polyurethane foams under static monotonic and multi-cycle loading, which causes the material’s plastic deformation. The studies were conducted for polyurethane foam samples with different weight contents of perlite powder, ranging from 0 to 10 mass parts. Infrared spectroscopy established heterogeneous inclusion of the perlite additive as a mineral filler into the polymer matrix without changing the main structural bonds of modified polyurethane foam (MPU). The change in the values of Young’s modulus, yield strength and relative plastic deformation depending on the quantitative content of the powder modifier was investigated. It was established that the addition of a powder modifier, perlite, contributes to an increase in the stiffness of MPU foam. The change in Young’s modulus under multi-cycle loading within each series of experimental samples was evaluated. The results confirm the effectiveness of perlite powder for modifying polyurethane foam not only for solar radiation protection, but also to increase the stability of the mechanical characteristics of rigid polyurethane foams.