Research Article
On the Tensile Tests of Polyurethane and Its Composites with Carbon Nanotubes
Figure 4
Tensile curves of five PU specimens at various stages of aging and with various thicknesses, interrupted by 30 s stress relaxation tests; . A/age of 190 days, t = 0.5 mm; B/252 days, t = 1 mm; C/192 days, t = 0.75 mm; D/32 days, t = 0.5 mm; E/32 days, t = 1 mm.