Extensional Mechanical Properties of Polyester‐ and Polyether‐Based Polyurethanes

摘要

An investigation of the extensional mechanical properties of a polyester‐based polyurethane (Texin 480 A Opaque 149004 B) and a polyether‐based polyurethane is described. Dynamic steady‐state tests were performed over a frequency range of 1000–8000 Hz and a temperature range of 50°–110°F for the polyester material held at a constant elongation of 105%. The experiments on the polyether were conducted at 110% initial elongation over a range of frequency of 200–1600 Hz, and a temperature range of 50°–110°F. The complex modulus was found for both materials and the reduced‐variable concept applied. Master curves for the moduli at a reference temperature of 510°R (50°F) are presented. Relaxation tests were performed on the same materials and the relaxation modulus determined. Finally, the relaxation spectrum was determined by using the data from the dynamic and relaxation experiments.