Improving the Competitiveness of Aramid Textile Materials Based on Mathematical Modeling and Analysis of Their Performance Properties

Advances in Raw Material Industries for Sustainable Development Goals

“…It also contains three physically based constants ðD 0 ; D ∞ ; b σ Þ and force-time function characterising the delay times τ σ (Rymkevich et al, 2013) Sufficient reliability and technical convenience follows from the analysis of the applicability of the considered simplest mathematical models of relaxation and creep used for the analytical description of the rheological properties of polymeric materials and the subsequently calculated prediction of loaded or deformable states of these materials. Due to the smallest number of parameters-characteristics, the simplicity of their determination from short-term experiments, and clarity of their physical interpretation, the developed methods seem to be promising not only for polymers but also for a number of other solid materials (Pereborova et al, 2019c).…”

“…where ε t -time-dependent deformation t, σ t -time-dependent stress t, E 0 -elastic modulus, E ∞ -viscoelastic modulus, normalised relaxation function that forms the basis of the mathematical model of relaxation (Pereborova et al, 2019c), integral relaxation kernel, A ε -parameter of the intensity of relaxation processes, logarithmic function of the relaxation times. The analytical form of the relaxation spectrum H � ετ can be obtained by the known formula (Pereborova et al, 2018c) � by successive approximations.…”

Systematic Analysis of the Deformational Properties of Polypropylene and Polyvinylidene Fluoride Surgical Materials

“…The initial modulus is 6.2 ± 3 GPa for PP thread and 2.6 ± 2 GPa for PVDF thread. The initial elastic modulus for PP thread is more than twice the corresponding modulus for PVDF thread, indicating that PP thread is more rigid than PVDF thread [13][14][15]. However, we note that the initial moduli for PP thread (6.2 GPa) and PVDF thread (2.6 GPa) are two orders of magnitude less than for the carbon-chain skeleton of the polymer molecules used to make these threads (200 GPa) [16][17][18][19].…”