Кафедра штучного інтелекту та математичного моделювання
Постійне посилання на фондhttps://repository.lntu.edu.ua/handle/123456789/57
Переглянути
2 результатів
Результати пошуку
Item type:Наукова стаття, The Effect of Ultraviolet on the Change in the Structural and Mechanical Properties of Polyurethane Foams(2025-12-01) Mikulich, Olena; Furs, Tatiana; Shemet, Vasylyna; Bondarskii, OlexandrThe article investigates the influence of ultraviolet (UV) on polyurethane foams' structural and mechanical characteristics. To assess the impact of changes and degradation of foam properties, studies were conducted for two groups of samples: those without exposure to UV and those exposed to natural UV for 3 months. According to the analysis of IR spectra, insignificant chemical changes in the structure of the outer surface of the samples were established as a result of three months of UV influence on the foam. No noticeable chemical changes were found in the inner part of such samples. Compression tests of samples of different groups were carried out under static loading to study the change in mechanical characteristics. Based on experimental tests, changes in the values of mechanical, strength, and deformation characteristics were investigated: Young's modulus, elastic strength, yield strength, and degree of deformation recovery. A conclusion was made about the resistance of polyurethane foam to ultraviolet influence for a period of up to three months.Item type:Наукова стаття, Powder Modifier Effect on the Mechanical Behavior of Polyurethane Foams(2026) Mikulich, Olena; Furs, Tetiana; Shemet, Vasylyna; Bondarskii, OlexandrThe 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.